Resolving Conflict and Overcoming Obstacles in Lorraine Hansberrys A R

Resolving Conflicts and Overcoming Obstacles in A Raisin In The Sun In the play, A Raisin In The Sun, induce tries to keep everything under control because she believes in her children and their dreams, however understands that they still need to learn and strengthen their values as they begin to realize their own aspirations. She is the head of the family around whom the conflicts gussy up and are resolved. After the death of her husband, Mother struggles to keep her family together by providing the support and guidance they need, and encouraging them to use good judgment and think of the family as a whole before make their decisions. As the family faces various obstacles, each seemingly more severe t... ...in the Sun. New York Signet, 1988. May, Elaine Tyler. Homeward Bound. New York. Basic Books, 1988. Patterson, pile T. Grand Expectations The United States, 1945-1974. New York. Oxford University Press,1996. Wilkerson, Margaret B. The spy Eyes and Feeling Heart of Lorrain e Hansberry. Black American Literature Forum 17.1 (1983) 8-13. Resolving Conflict and Overcoming Obstacles in Lorraine Hansberrys A RResolving Conflicts and Overcoming Obstacles in A Raisin In The Sun In the play, A Raisin In The Sun, Mother tries to keep everything under control because she believes in her children and their dreams, yet understands that they still need to learn and strengthen their values as they begin to realize their own aspirations. She is the head of the family around whom the conflicts arise and are resolved. After the death of her husband, Mother struggles to keep her family together by providing the support and guidance they need, and encouraging them to use good judgment and think of the family as a whole before making their decisions. As the family faces various obstacles, each seemingly more severe t... ...in the Sun. New York Signet, 1988. May, Elaine Tyler. Homeward Bound. New York. Basic Books, 1988. Patterson, James T. Grand Expectat ions The United States, 1945-1974. New York. Oxford University Press,1996. Wilkerson, Margaret B. The Sighted Eyes and Feeling Heart of Lorraine Hansberry. Black American Literature Forum 17.1 (1983) 8-13.

The Effects of Marijuana :: essays papers

The Effects of MarijuanaMarijuana is a mood altering or psychoactive do drugs that has umpteen nicknames, such(prenominal) as pot, weed, ganja, sensi, herb, and others. It is an ancient drug that dates back to hundreds of years to Asia. Many cultures have used it during meditation, religious worship, and for intoxication. Marijuana itself comes from the Indian Hemp plant. It is the third approximately widely used drug in the United States, according to a survey taken in 1988, and it is the number one illegally used drug in the United States. Marijuana is so popular that an estimated one out of every three people in the US have tried it and nigh 44% of US high school students have smoked it. Marijuana users are not easily detectable, nor is the drug just used in one area of society. The Indian Hemp plant is found all over the world, including the US. There are three different types of Indian Hemp. They are halter Sativa, Cannabis Indica, and Cannabis Rudderalis. These three plants vary in size and mood altering effect. The hemp plant has many uses and has been farmed for centuries. Marijuana can be taken in three ways, by eating, made into a tea, or smoking (the most popular). Smoking it can be done three ways, through a pipe, a joint, blunt. A joint is a rolled piece of paper that is twisted at the ends. A blunt is normally an emptied cigar wrapper filled with marijuana. In a blunt you can fit much more marijuana. Though a blunt isnt always purely marijuana, it can be mixed with other drugs such as angel dust.The results are varied when someone smokes marijuana. Different people entrust get different results, and certain types of cannabis can cause different effects. The amount of THC (marijuanas main active chemical) may also change the result. If alcohol, or other drug use is occurring while smoking marijuana, the effect could be different. A first time marijuana smoker will probably feel no effect. A chronic or heavy user will get a high (intoxication). When a person is high, normal sights, sounds, tastes, or events can seem very funny or interesting. When intoxicated, time seems to pass a lot slower. To the user, minutes will seem like hours.

The Economic Effects Tourism Has on New Zealand Essay -- New Zealand T

The Economic Effects Tourism Has on New ZealandThe following report provides an true and informative overview of the nature of tourism, its history and growth, the structure of the New Zealand industry and the impact of tourism from a New Zealand perspective. The report will draw a termination which Highlights area of consideration in tourism planning.Conclusion and RecommendationsFor New Zealand tourism has a lot to offer except at the same time, care has to be taken not to mistreat it. The social and cultural impacts of tourism on New Zealand so far fuck off been on the whole beneficial but as tourism continues to grow this could change. Non-economic benefits of tourism are maximized when visitors and hosts share mutual interests and when trade is relatively small. However these factors limit potential tourist markets and income. One resolution to this problem could be promotion of New Zealand as a high quality destination at a higher price, i.e. less tourists spending more than than silver.New Zealand tourism is largely reliant on Eco-tourism so to maintain the tourism industry it is imperative that our environment is conserved. However tourism itself can give birth negative effects on the environment. The tourism sector must act responsibly in its use of the environment and any use must be sustainable.It is the economic effects of tourism which bring the most benefit to the host nation. Tourism is a low import user which means more of the money earned here stays here. The government is earning money through tourist taxes such as the airport tax, increased export earnings and income tax gross from people employed by the industry. A balance must be struck between these benefits and associated negative impacts on the community and the environment.If New Zealand is to see more growth in tourism we must try and make the country more attractive to visit. More flights, low visa requirements, favorable exchange judge are all facilitators that will make Ne w Zealand more appealing. With a high level of promotions overseas that will motivate tourists to think of our country as a destination which will be able to satisfy their needs.The Nature of TourismThere is not really a universally accepted definition of tourism. In 1994 the World Tourism Organization (WTO) revised its definition. It says the tourism comprises of the activities of persons travelli... ...ourism has an influence on most areas of society, employment, environment, health, economic stability and quality of life. Therefore it is the concern of governments, the mankind sector, is to ensure the negative consequences is minimized. At the 1968 UN Conference on International Travel and Tourism it was made clear the government intervention and management is required for the glitter running tourist activities between countries.In New Zealand the biggest participants in creating the creating the tourism product are from the private sector, that is individual operators like ai rlines, accommodation chains, attractions and tour operators. These sectors have their own organizations. For example hotels are represented by the Hotel Association of New Zealand (HANZ). The sales sector has groups like the travel agents Association of New Zealand or the inward Tourism Organizations Council. In Turn they all feed into the New Zealand Tourism Industry Association (NZTIA). The NZTIA can then represent their interests to the New Zealand Tourism scorecard (NZTB) , which is the countrys national tourism Organization, or the ministry of commerce, which is responsible for tourism legislation.

Hamlet :: essays research papers

William Shakespeare (1564-1616) was born in Stratford-upon-Avon, England. He was the son of John and Mary Shakespeare. William attended his towns local grammar school at age six and gradational ten years later. When he was eighteen, he married a woman named Anne Hathaway who gave birth to twins, Hamnet and Judith. Hamnet drowned a few years later. It is said that William named his famous play settlement after his son and included a drowning scene in his honor. After the loss of his son, William left his family behind and headed for London to write plays. He was a poet and playwright. He wrote many famous plays, including Macbeth, Hamlet, and Romeo and Juliet. His stories were very popular with the English people because some of them were about English kings, like Henry IV. One of the characters from Henry IV was Falstaff, a drunk and crude knight. People liked him so much that William wrote another play using Falstaff, entitled The Merry Wives of Windsor. Shakespeare lived during t he Renaissance period, and was one of the most authoritative playwrights of his time.Hamlet is set in medieval times and relates the story of Hamlet, who is the son of the dead King of Denmark, which appears as a ghost. The ghost appears at midnight and hints to Hamlet and his 2 friends Horatio and Marcellus about his murder. Hamlets mother, Gertrude, quickly marries Hamlets Uncle Claudius barely before the Kings body is even cold. Hamlet finds out that Claudius poisoned his come while he was sleeping to gain control of the throne. Hamlet confronts his mother about knowing about the murder of his father, and her affair with Claudius. Claudius attempts to kill Hamlet on a vacation voyage to England, by getting Rosncrantz and Guildenstern, Hamlets boyhood friends to carry a letter to the King of England to chop off Hamlets head. Hamlet intercepts the letter, and sends a letter to the King of England, telling him to immediately cut off the heads of the messengers. Hamlet then plots to kill Claudius because He killed my king and whored my mother. Laertes is allowed a affaire dhonneur against Hamlet to revenge his father, Polonius, murder. Halfway into the duel, Claudius toasts the duelers, and drops a poison-coated pearl into the wine as an inducement for Hamlet to finish the drink. However, Gertrude decides to drink it herself.

Americas Transition from a Regional to a World Power Essay -- America

Americas Transition from a regional to a World force outBetween the years 1875 through 1920 the united States of America was able to secure itself as a major sphere power. This was easy to do after the industrial Revolution and the Progressive movement because the ii more or less important qualities needed to be able to accomplish moving from a regional to a world power existed during this time period an sparing need of resources and mass production using technology, especially with transportation. Ideology and culture also played important roles in Americas rise to power. As industrialist Andrew Carnegie describes, The old nations of the earth creep on at a snails pace but the unite States thunders one-time(prenominal) with the rush of the express train (Norton 608). The first, and arguably the most important, event that helped to bring about the United States new status was the Spanish American War. It was extremely vital for the United States to establish itself as h aving colonies in parliamentary procedure to be a part of the world. Additionally, most Americans were in favor of expansion as lo... Americas Transition from a Regional to a World Power Essay -- AmericaAmericas Transition from a Regional to a World PowerBetween the years 1875 through 1920 the United States of America was able to secure itself as a major world power. This was easy to do after the Industrial Revolution and the Progressive movement because the two most important qualities needed to be able to accomplish moving from a regional to a world power existed during this time period an economic need of resources and mass production using technology, especially with transportation. Ideology and culture also played important roles in Americas rise to power. As industrialist Andrew Carnegie describes, The old nations of the earth creep on at a snails pace but the United States thunders past with the rush of the express train (Norton 608). The first, and arg uably the most important, event that helped to bring about the United States new status was the Spanish American War. It was extremely vital for the United States to establish itself as having colonies in order to be a part of the world. Additionally, most Americans were in favor of expansion as lo...

Americas Transition from a Regional to a World Power Essay -- America

Americas Transition from a Regional to a World PowerBetween the years 1875 through 1920 the United States of America was able to bushel itself as a major valet de chambre power. This was easy to do after the Industrial Revolution and the Progressive movement because the two most important qualities unavoidable to be able to accomplish go from a regional to a world power existed during this time period an economic need of resources and mass end product using technology, especially with transportation. Ideology and socialisation also played important roles in Americas rise to power. As industrialist Andrew Carnegie describes, The old nations of the earth crazy on at a pull togethers pace but the United States thunders past with the rush of the express train (Norton 608). The first, and arguably the most important, event that helped to bring closely the United States new status was the Spanish American War. It was extremely vital for the United States to establish itself as having colonies in order to be a function of the world. Additionally, most Americans were in favor of magnification as lo... Americas Transition from a Regional to a World Power Essay -- AmericaAmericas Transition from a Regional to a World PowerBetween the years 1875 through 1920 the United States of America was able to secure itself as a major world power. This was easy to do after the Industrial Revolution and the Progressive movement because the two most important qualities needed to be able to accomplish moving from a regional to a world power existed during this time period an economic need of resources and mass production using technology, especially with transportation. Ideology and culture also played important roles in Americas rise to power. As industrialist Andrew Carnegie describes, The old nations of the earth creep on at a snails pace but the United States thunders past with the rush of the express train (Norton 608). The first, and arguably the most important, event that helped to bring about the United States new status was the Spanish American War. It was extremely vital for the United States to establish itself as having colonies in order to be a part of the world. Additionally, most Americans were in favor of expansion as lo...

Pauline Breedlove Life

Character Analysis Paper Pauline Breedlove (Polly), one of the main characters of the story, who is also the mother of Pecola and Sammy Breedlove and teammate of Cholly Breedlove, can be seen as a violent figure towards her family and seems to have a negative out calculate on life. The reason behind all(a) this behavior can be better understood if we were to take into account of her past, the time frame this story was in, and which then would bring us to how its affecting others virtually her. Pauline always seemed to have been troubled.It all began with her foot that she injured as a little girl, she had gotten a nail in it which then left her with a limp. After she started limping her dream of becoming an actress seemed unrealistic because of her flaw. Things didnt really get oft better from that either. She later blocked up in Lorain, Ohio with Cholly where she becomes solitary and isolated, she doesnt fit in with the northern women and understand their mannerism. Later we f ind out one day while she was at the movies she lost her front tooth from thorny down too hard on a piece of candy.Which in the end lead her to believe she was ugly and her husband didnt help much since he was under the influence of alcohol most of the time. The limp, the loss of her tooth, and the way she felt nearly her current living situation caused her to not care about herself and its showed in the way she started caring for her house and the her soon to be family. The story is set in the 1940s where blacks werent looked upon as that great. At the time Pauline had quit a bit of obstacles blocking her way of becoming an actress.The limp, her missing tooth, her skin color, and looks. Her physical appearance wasnt up to the ideal beauty which was flaxen hair, blue eye eyes, and light skinned. Since the story takes places back when racism was still relevant there was nothing for a psyche like Pauline to look up to, so what she lived with everyday and seeing herself made her to grow self hatred for herself. The self hatred she had made an impact on the people she dealt with in her life.The anger she had deep within her self for not being good enough resulted in the mistreatment of her children and neglected her duties of being a good wife and mother. The backwash of herself as ugly lead to believing her family were ugly too. With the way she viewed life also made her treat her job a certain way, Pauline believed that if she couldnt make herself beautiful treating her profession would replace that. By working for the Fishers, a white house hold, it caused her to live in a somewhat fantasy world.As opposed to the love and care she showed towards the Fisher family her actual family never received that type of treatment, beatings, fights, and arguments were a constant thing in the Breedlove household. So in the end the reflections on a persons past can shape them to be who they are. For Mrs. Breedlove it is easily seen that past events caused her to have neg ative effect on her and the others snarly in her life, and with it being back when times were hard especially for African Americans it only made the situation worse, but it all shaped Pauline Breedlove into the person she is.

Can Technology Replace Teachers Essay

TV, ready reckoners hold up fully integrated into urban life in many spheres same(p) education, entertainment, and commerce, and therefore, some people consider that the technology such as multimedia teaching would replace teachers in class. I would say this does not sound truly convincing because the superiority of the teachers are obvious. The first and most apparent advantage that face-to-face conversation is a vital ability for the environment of the social on the job(p) is clear.Teachers give students direction to have a good grasp to work in the team or respect each other. It is possible for one to have a video communication with teacher to achieve that, however, the meaning of much of what we say depends on our body language and tone of voice which can not be transmitted by the computers. The interaction between teachers arid students is the core of teaching process. Additionally, it is generally thought that multimedia always connects with Internet which is a ambiguous sword.The Internet with innumerable news sources about curriculum let us make the paradox of choice. For instance, we downland a mass of materials for TOEFL tests but do not cheat which one to start. Teachers play significant roles to guide our study, and they can tell us where we begin with, what we should do, and which reference we should choose, hence their proposal always make a immense difference especially in a brand new discipline. As a facilitator ,teacher can make us learn efficiency.Whats more, students,with low self-control, also easier to indulge in bad or rather faulty information and act on it. Teachers also play significant roles in supervising students. In conclusion, the computer has been widely used in class,it cannot replace the role of teachers who impersonated an essential part of modern education. Nevertheless,multimedia teaching facilitates our education like PPT teaching which can avoid the codswallop dust. Teachers can use this trait to mend and consumma te our education.

Confidence and Innocence Through Point of View

John Updikes well-known short story, A & P, employs a unique form of narrative, utilizing the first person point of view.The themes of innocence and confidence of the youth intertwine in Updikes story, through a athletics in narrative tone, as made executable by the first person point of view. As an effect of this narrative form, the story begins abruptly In walks these tierce girls in nonhing but bathing suits. The tension that will slowly build up as the story progresses is given right outside(a) at the narrations first blow.Followed by the first sentence is a statement from the persona, which serves as a device to establish the storys setting. At this point, a camera is set up for us in the place where the story happens. The voice in the narrative serves as the set of eyeball by which we witness all events taking place. Set in the A & P grocery store, the story unfolds in a setting of complex complex body partshelves with items lined up and several identical aisles.Perhaps , with this focused and limited set of eyes, the first person point of view allows the reader to get a alter description of the A & Ps surroundings Im in the third check-out slot, with my back to the door . . . Throughout the story, we meet char modus operandiers and witness events through this perspective.Updikes narration, however, is not just unique in terms of point of view. The choice of perspective also enables the reader to hear a distinct voice. go with by a pair of eyes is a voice and tone that contributes to strengthening the realistic feel of the story. It is noticeable that the language used by the occasion is very conversational, making it feel like the voice connects directly to the reader. Not only does it tell the story it slowly forms a personality, which, in this case of use the first person point of view, is not excluded from the storys turn of events.In A & P, we witness an incident caused by three teenage girls in bathing suits from the perspective of Sammy, a nineteen-year-old boy working at the check-out counter. It is interesting that his name is not revealed until the late middle portion of the story. Nevertheless, his character has already been accomplished at the very beginning, where we hear his voice and vi autoiously experience the story. To further explore this point, let me cite a few lines, which contribute to establishing Sammys character.Seeing the three girls in bathing suits, he immediately focuses his attention to one girl, which he refers to as a chunky kid. Here, by noting his word choice, Sammy already appears to us as a free-spirited teenager. This is reiterated as he comments on the customer who complains as Sammy rings the purchase a second time Shes one of these cash-register-watchers, a witch around fifty with rouge on her cheekbones and no eyebrows, and I know it made her day to trip me up. Shed been watching cash registers forty years and probably neer seen a mistake before.These lines are dabbed with a sen se of annoyance towards elders, and in this case, an old lady. Later on in the story, we get the same feel in his somewhat mocking remark . . . women generally put on a shirt or shorts or something before they get out of the car into the street. And anyway these are usually women with six children and varicose veins mapping their legs and nobody, including them, could care less.This tone, which brings with it a sense of confidence freedom of spirit, also shows us the innocence understructure the personalityhis opinions are quite shallow, leaning towards trivial matters. This overall tone contributes and prepares us for the shifts that occur in the story. The finality in Sammys tone falters when he begins to speak of Lengel, the single figure of authority in the story. More and more, the compute presented to us of Lengel reveals Sammys innocence. And indeed, the storys conclusion confirms it.The presence of the three girls in A & P also reflects the innocent confidence of the youth . Baring all, they brazenly enter into a place, not caring that their outfits dont blend in. At first, it appears to us as a dare, as something that Queenie perhaps suggesteda rebellious act, which could probably be an act against authority, intended to project superiority over rules and adults.However, this queen-like image of strength also falters at the entrance of Lengel into the story. Lengel obviously represents authorityas manager and as Sunday School teacher. Firm in his tonenot defensive or angry, nor is he loud and uncontrolled, he calls out the unfitting clothing worn by these three young ladies.As he speaks, we feel the relentless contrast of tone between him and the teenagers in the story. Right after this, one of the girl mentions her mother as an excuse My mother asked me to pick up a jar of herring snacks. Immediately, the brazen air to Queenie vanishesshe appears to us as a little girl hiding under her mothers skirt. By inserting a figure as Lengel into the narrati ve, Sammys tone is helplessly muffledas if he suddenly gives in to how things areand not as how he perceives things to be.The events that succeed feel like a gradual crash. Impulsive as he is, Sammy decides to play the role of an unsuspected hero. And the way he narrates his story implies that his next act is only seemingly brave, defiant, and strong.He makes his motives clear The girls, and whod blame them, are in a hurry to get out, so I phrase I quit to Lengel agile enough for them to hear, hoping theyll stop and watch me, their unsuspected hero. Not knowing how to handle the situation, he puts up a front, faltering more and more I started to say something that came out Fiddle-de-doo. Its a saying of my grand- mothers, and I know she would have been pleased.Again, figures of authority are projected in the storythe mention of his grandmother, for instance. Soon after that, Lengels input to Sammys impulsiveness makes him look even more innocent and youngan image which veers away from the initial confidence suggested by the tone made possible by the narrations first person point of view Lengel sighs and begins to look very patient and old and gray. Hes been a friend of my parents for years.Sammy, you dont want to do this to your Mom and Dad, he tells me. Parents once again come into the picture. And the mockery thrown by the

Political Science Coursework Essay

Newsmap2A No, the intention of the news aggregator is to be biased because what they argon presenting in the website is the biased pattern of news information and presentation.2B According to them (the owners of the website), it the website is vox populi to ironically accentuate the bias of it news (Newsmap). They are biased in that they are showing the biased patterns of news information and presentation by showing the primal connections and relationships between bits and pieces of news information and putting them altogether to present a tree map.Date of Access Saturday, litigate 29, 2008 748 A.M4A U.S. Nation pretend Arrested in Virginia Highway Shootings4AA The alleged person responsible for the Highway Shootings in the state of Virginia was arrested by the states police department. Reports have confirmed that the odd is a 19-year-old who is facing a criminal case due to an other(a) shooting that happened the day before that in Waynesboro. Slade Allen Woodson is to a fault the singular suspect in the highway shootings in Charlottesville where six vehicles were hit and two batch obtained minor injuries. Prior investigation led the police to trace a vehicle that was seen in surveillance tapes at the scene of the crime to be owned by Woodson. (Grynbaum)Date of Access Saturday, March 29, 2008 1001 AM4B U.S. contrast American to sketch Normal Schedule4BB Due to inspection and repairs, American Airlines, Inc. was forced to cancel some of their courses yesterday. The airline conducted repairs for four of the level(p)s yesterday morning and continued general plane inspections in the afternoon. According to the airline representative, almost half of the 300 planes needed modifications. Delta Airlines, Inc. has also completed plane inspections however, they finished earlier than American allowing them to proceed with their Friday flight schedule. Southwest Airlines Co. and American Eagle also conducted the same inspection earlier than the aforementioned t wo. The inspection is part of the FAAs program of aircraft safety checks. (East Bay Business times)Date of Access Saturday, March 29, 2008 1222 PM4C U.S. Technology Shuttle Crew Reflects on Marathon Mission4CC The astronauts from the space shuttle sweat has landed earth last Wednesday night. The said mission, composed of seven astronauts, was the longest shuttle expedition. The astronauts shared their enjoyable experiences while they were still in the shuttle and also their trip to earth and their landing after staying for such a long time in space. They all agreed that they find it difficult to adjust to the dryness here on earth. Aside from their previous revelations, they also revealed their experiences while they were still in space. (Malik)Date of Access Saturday, March 29, 2008 1005 AM4D U.S. Health U.S. to involve Drug for Suicide Links4DD The alleged connection between Singulair and suicide stirred up investigation in the Food and Drug Administration (FDA). Singulair i s overlap manufactured by Merck, which markets itself for allergies and asthma. Due to numerous attacks on the side effects of the drugs, Merck has placed great efforts in repackaging their product in order to include approximately several side effects, risks involved, anxiety and depression, etc. in the drugs literature. The FDA focused on the case as soon as they received numerous reports from people who have used Singulair and have experienced dangerous side effects. The results of the study will be known after nine months of investigation. (The Associated Press)5 I cannot help but think about the politics involved between business advertising and the media. In the article American to Resume Normal Schedule, there seems to be substantial evidence that proves the link between businesses and media. From the title of the article itself, the article is supposed to be informing the public of the flight schedules in the American Airlines, Inc. Moreover, the article is supposed to re veal why there were flight cancellations and the company should have used the media opportunity to apologize for any inconveniences that they might have caused to the public. These, I think, should have been the content of the article because of its title, and because of the need to inform the public about the issues behind the flight cancellations.However, the article was used as an advertising strategy for the aircraft business, particularly the Oakland International Airport (OIA). First, three airlines who serve OIA were mentioned in the article especially their efforts to adhere to the safety check programs of the FAA. Second, despite added information that the FAA is conducting safety checks for all major(ip) airlines, only the airlines that are connected with OIA were mentioned. Third, since Southwest Airlines Co. is the most dominant carrier among the three making it the most bankable airline, it is only strategic to market other airlines, such as the American Airlines, Inc. Thus, the title and that impression that it is trying to exude.6 Yes, in a political nine, being aware of the news and current events is important.6A Basing from my solvent to the article about American Airlines, Inc. and advertising, being aware of all the current information that is going on nowadays is very important, especially when looking at a particular issue in a 360-degree angle, because it is instrumental in reading between the lines and ground what is really going in society. Through the news, people are able to see the politics there is in all aspects of society.Buzztracker7A The primary objective of Buzztracker is to utilize global news releases to present an illustration of locations that are interrelated. Although places in the world are separated by distance, the buzztracker shows their connection through a diagram and through the news that these countries share. (Buzztracker)7B Date Accessed Saturday, March 29, 2008 1225 PMMost Prominent Location Washington7C Th e news event that brings Washington to the forefront is the issue published by Express India, wherein it advocated the support the bush administration should give to the new Pakistani government. For some, this would somehow alleviate harsh judgments on the U.S. government by its relationship with previous Pakistani president, which was tainted with trick and misgivings. The Bush administrations ability to lean towards democracy and help Pakistan could change how people see the U.S. government.7D The buzztracker is a great help in understanding the significance of one location to others. It keeps people on track about the global community and gives them a clear understanding of what is happening in society by relating it to external situations outside the country. The top Location is significant in world affairs it enters the news because of the significant role it is playing the world. Washington is the quarter of the U.S. government, which we all know is active and influential i n almost all parts of the world.Works CitedThe Associated Press. (28 March 2008). U.S. to Study Drug for Suicide Links. Retrieved fromThe New York Times Company. 29 March 2008. .Buzztracker. (2007). Buzztracker. Retrieved from Craig Mod. 29 March 2008..East Bay Business Times. (28 March 2008). American to Resume Normal Schedule. Retrievedfrom the American City Business Journals, Inc. 29 March 2008. .Grynbaum, Michael. M. (29 March 2008). Suspect Arrested in Virginia Highway Shootings.Retrieved from The New York Times Company. 29 March 2008. http//www.nytimes.com/2008/03/29/us/29cnd-virginia.html?_r=1&ref=us&oref=sloginMalik, Tariq. (27 March 2008). Shuttle Crew Reflects on Marathon Mission. Retrieved fromMicrosoft. 29 March 2008. .Newsmap. (2008). Newsmap. Retrieved from Markos Weskamp. 29 March 2008..

Hydraulic Design of Small Hydro Plants

Version 2 STANDARDS/MANUALS/ GUIDELINES FOR SMALL HYDRO DEVELOPMENT Civil whole kit and boodle hydraulic concept Of Sm whole Hydro brings Lead Organization Sponsor Alternate Hydro null Center Indian Institute of Technology Roorkee Ministry of New and Renewable Energy Govt. of India whitethorn 2011 AHEC/MNRE/SHP Standards/ Civil whole kit Guidelines For hydraulic finis Of low Hydro Plants / may 20111 1. GUIDELINES FOR hydraulic DESIGN OF SMALL HYDRO PLANTS This surgical incision proffers stocks and happenlines on the conventioning of the peeing conductor system of rules.This system includes layer working and usance, feeder epithelial duct, desilter (if overtopd), power ignoreal or alternative conveyance structures (culverts, organ pipelines, tunnels, etc), forebay tank, sluice and surge tank (if essential) up to the main course of the turbine, tailrace kindleal downstairs the turbine and related ancillary working. 1. 1 HYDRAULIC DESIGN OF chief WORKS In g eneral spot whole kit and caboodle ar composed of three geomorphological servings, deflexion dam, intake and seam load sluice. The functions of the top works atomic number 18 Diversion of the required project hang up from the river into the piss conductor system.Control of repository. alluvium handling. Typically a dubiousness pond reservoir is formed upriver of the intellect works. This reservoir whitethorn be used to provide daily pondage in support of peaking operation or to provide the control passel necessary for turbine operation in the water level control path. This latter topic would apply where the penstock overtakes its water directly from the head pond. Sufficient volume mustiness be provided to support these functions. There are three qualitys of head works that are widely used on mini and small hydro projects, as below Lateral intake head works Trench intake head worksReservoir / canal intakes Each type volition be discussed in turn. 1. 1. 1 ex t abolish Works with Lateral Intakes ( venial Hydro) level works with lateral intakes are typically applied on rivers transporting significant amounts of depositary as bed load and in suspension. The functional objectives are To divert bed-load away from the intake and flush downstream of the dam (the bed load flushing system should be operable in both(prenominal) continuous and intermittent modes). To decant relatively clean surface water into the intake. To arrest floating debris at intake trashracks for removal by manual(a) raking.To guardly put down the fig flood without causing unacceptable upriver flooding. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For hydraulic founding Of picayune Hydro Plants /whitethorn 20112 The next site features promote favourable hydraulic conditions and should be studyed during site endurance The intake should be located on the outside of a river bend (towards the end of the bend) to benefit from the spiral current in the river tha t moves clean surface water towards the intake and bed load away from the intake towards the centre of the river.The intake should be located at the head of a steeper section of the river. This will promote removal of material flushed through the dam which may other accumulate downstream of the flushing contrast and impair its function. Satisfactory foundation conditions. Ideal site conditions are rare, thus tendency will require compromises surrounded by hydraulic requirements and constraints of site geology, accessibility etc. The followers guidelines assume head works are located on a straight reach of a river. For classic projects or unusual sites hydraulic model studies are recommended.A step by step practice approach is recommended and objective parameters are suggested for guidance in goal and layout studies. Typical layouts are shown in Figures 2. 2. 1 to 2. 2. 3. 1. 1. 2 Data Required for design. The adjacent data are required for design Site hydrology report as s tipulated in Section 1. 3 of this Standard giving Qp ( adjust run) Q100 (design flood conflate, small hydro) Q10 (design flood flow, mini hydro) (data on suspended sediment loads) Cw H-Q Curves (W. L. rating curves at diversion dam) Topographic mapping of the site including river bathymetry covering all head works structure sites.Site geology report. 1. 1. 3 Site Selection Selection of the head works site is a practical decision which involves weighing of several factors including hydraulic desiderata (Section 2. 2. 1/1. 0), head optimization, foundation conditions, accessibility and constructability factors. Given the importance of intake design to the overall performance of the plant it is recommended that an experienced hydraulic engineer be consulted during studies on head works layout. 1. 1. 4 Determination of Key Elevations AHEC/MNRE/SHP Standards/ Civil Works Guidelines For hydraulic externalize Of Small Hydro Plants / may 20113For the illustrative example Qp = 10. 0 m3/s mould V0 = 0. 5 Q0. 2 (= 0. 792, say 0. 80 m/s) (= 12. 5 m2) A0 = Q ? V0 A0 H= (= 1. 77 m, say 1. 80 m) 4 strickle L = 4H (= 7. 08 m, say 7. 0 m) ye = greater of 0. 5 yo or 1. 5 m (= 1. 80m) yd = L. S (= 0. 28 m) NOL = Z0 + ye + yd + H NOL = 97. 5 + 1. 80 + 0. 28 + 1. 80 (=101. 38m, say 101. 50 m) Sill = NOL H (= 99. 7m) Crest of weir or head pond NOL = 101. 5 m Height of weir = 4. 0 m These initial key elevations are preliminary and may have to be adjusted later as the design evolves. 1. 1. 5 dot Works LayoutThe entry to the intake should be aligned with the river rim to provide smooth approach conditions and minimize the occurrence of undesirable swirl. A guide wall acting as a transformation between the river bank and the structure will usually be required. Intake hydraulics are raise if the intake face is slightly tilted into the flow. The orientation of the intake face depends on river bank topography, for straight river reaches the recommended values for tilt var y from 10o to 30o depending on the author. When this fish becomes too large the intake will attract excessive amounts of sediment and floating debris.It is recommended that the sill level of the intake is kept sufficiently risqueer than the sill level of the under sluice. The under sluice should be located adjacent to the intake structure. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For hydraulic number Of Small Hydro Plants /May 20114 For development of the head work plan, it is recommended that the following parameters be used for layout Axis of intake should between 100 to 105 to bloc of diversion structure The actual object may be finalized on the basis of model studies. Divide wall, if provided, should cover 80% to 100% of the intake. win flushing flow equal to twice project flow then approximate the breadth and bill of the flushing gate from orifice locution, Example should be in appendix. Qf = 0. 6 ? 0. 5W2 Where Qf = flushing flow W = gate width H = gate heig ht (= 0. 5W) Yo = normal flow depth as shown in 2. 2. 1. 1/2. 0 Sill should be straight and perpendicular to the flow direction. In the sample design (Fig. 2. 2. 1. 1) the axis of the intake = 105 & Qf = 2. 0? 10. 0 = 20m3/s ? 20. 0 = 0. 6 ? 0. 5 W2 ? W = 2. 8 m (say 3. 0m) and H = 1. 5 m. 1. 1. 6 Flood Handling, MFL and Number of provide.For small hydro a simple overflow diversion weir would be the pet option if flood purloin would non cause unacceptable upstream flooding. For purpose of illustration, the following design data are fictional ( turn back Figure 2. 2. 2) innovation flood, Q100 = 175 m3/s A review of reservoir topography indicated that over bank flooding would occur if the flood water level exceeded 103. 0 m. Select this water level as the MFL. This provides a flood surcharge (S) of 1. 20 m. Assume weir coefficients as below Gate, Cw = 1. 70 sill on slab at river bottom. Weir, Cw = 1. 0 -ogee compose. Assume gate W/H ratio = 12 H = 4. 0 m ? W = 4. 8 (sa y 5. 0 m) MFL. = NOL + 1. 50 (= 103. 0m) Qgate = Cw. W. (MFL ZS)1.. 5 Qweir = Cw. Lw. S1. 5 Capacity check for MFL = 103. 0 m No. of Length of Overflow QG Gates Section (m) (m3/s) 0 35. 0 0. 0 1 29. 0 109. 6 QW (m3/s) 82. 8 68. 6 QT (m3/s) 82. 8 178. 2 175 AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic function Of Small Hydro Plants /May 20115 Therefore one gate is sufficient. Where MFL = Maximum flood level (m) NOL = Normal operating level (m) S = flood surcharge supra NOL (m)W = width of gate (m) H = height of gate (m) ZS = elevation of gate sill (m) = weir coefficient (m0. 5s-1) Cw QG, QW, QT = gate, weir and total flows The flow capacity of the sediment flushing gate may alike be included in calculating flood handling capacity. 1. 1. 7 Diversion structure and spillage Plains Rivers Stability of structures founded on alluvial foundations typical of plains rivers, is governed by the magnitude of the exit gradient. The slender gradient is approximately 1. 0 and shall be reduced by the following safety factors Types of foundationShingles / cobbles Coarse backbone Fine sand Safety factor 5 6 7 Allowable Exit Gradient 0. 20 0. 167 0. 143 Also diversion structures on plains rivers will normally require stilling basins to dissipate the vitality from the fall a torment the diversion structure before the water can be returned safely to the river. Design of diversion weirs and barrages on permeable foundation should follow IS 6966 (Part 1). Sample calculations in Chapter 12 of Fundamentals of Irrigation Engineering (Bharat Singh, 1983) explain determination of uplift force distri andions and exit gradients.Further details on structural aspects of design are habituated in Section 2. 3. 3 of this Standard. Mountain Rivers Bedrock is usually found at relatively shallow depths in multitude rivers permitting head works structures to be founded on rock. Also the beds of mountain rivers are practically boulder paved and are much more resistant to e ating away than plains rivers. Therefore there may be no need for a stilling basin. The engineer may consider refer blocks on the downstream apron or simply provide an angled lip at the downstream end of the apron to flip the flow away from the downstream end of the apron.A cut-off wall to bed rock of courtingable depth should AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 20116 to a fault be provided for added protection against undermining by scour. The head works structures would be intentional as gravity structures with enough mass to resist flotation. For low structures height slight than 2. 0 m anchors into bottom fundamental principle may be used as the prime stabilization element in dam design. Stability and stress design shall be in accordance with requirements of Section 2. 3. 3 of this Standard. 1. 1. 8 Sediment Flushing Channel To be reviewedThe following approach is recommended for design of the flushing channel S elect flushing channel flow capacity (Qf) = 2? Qp Estimate maximum size of sediment entering the pocket from site data or from transport capacity of approaching flow and velocity. In case of diversion weir without gates assume sediment accumulation to be level with the weir crest. (Assume continuous flushing with 3? Qp entering the pocket, for this calculation). Establish entrance sill elevation and channel vend assuming an intermittent flushing mode (intake closed) with Qs = 2Qp, critical flow at the sill, supercritical flow downstream (FN ? 1. 0) and a reservoir operating level 0. 5m below NOL. tick slope of channel to provide the required scouring velocity, using the following formula which incorporates a safety factor of 1. 5 i = 1. 50 io d 9/7 i0 = 0. 44 6 / 7 q Where io = critical scouring velocity d = sediment size q = flow per unit width (m3/s per m) Verify that flow through pocket in continuous flushing mode (Qs = 3Qs) will be sub critical, if not lower entrance sill elev ation further. Determine height of gate and gate opening establish on depth of flow at gate location and alike(p) gate width. Increase the in a higher place theoretical gate height by 0. 5 m to ensure unrestricted open channel flow through the gate for intermittent flushing mode and a flushing flow of 2 Qp. For initial design a width to height ratio of 21 for the flushing gate is suggested. 1. 1. 9 Intake/Head Regulator In intake provides a transition between the river and the feeder canal. The main design objectives are to exclude bed-load and floating debris and to minimize head losings. The following parameters are recommended Approach velocity at intake entrance (on gross sphere of influence) 0. 20 Ve = 0. 5 Q p m / s For trashracks that are manually cleaned, V should not exceed 1. 0 m/s.AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 20117 Convergence of side walls 2. 51 with rate of profit in velocity not exceeding 0. 5 m/s per linear m. Height of sill above floor of flushing channel (ye) = greater of 1. 5m or 50% flow depth. The floor of the transition should be sloped down as required to join the countermand of the feeder canal. bust that the flow velocity in the transition is adequate to observe deposition in the transition area. If sediment loads are very high consider installing a vortex silt ejector at the downstream end of the transition. Provide coarse trashracks to guard entry to the head gate. The trashrack would be designed to step floating debris such as trees, branches, wood on other floating objects. A cleared spacing of 150 mm between bars is recommended. Trashrack detailed design should be in accordance with IS 11388. The backtrack of the feeder canal shall be obstinate taking into friendliness head passinges through the trashrack and form losses through the structure. Friction losses can be omitted as they are negligible V2 Calculate form losses as H L = 0. 3 2 2g Where V2 = velocity at downstream end of condensation.Calculate trashrack losses as 4/3 V2 ?t? H L = K f ? ? . Sin? . 2g ?b? Where Kf = head loss factor (= 2. 42 assuming angulate bars) T = thickness of bars (mm) B = clear bar spacing (mm) ? = angle of inclination to horizontal (degrees) V = approach velocity (m/s) 1. 1. 10 References on Lateral Intakes and Diversion Weirs. IS Standards Cited IS 6966 (Part 1) IS 11388 USBR (1987) Singh, Bharat Nigam, P. S. Hydraulic Design of Barrages and Weirs Guidelines Recommendations for Design of Trashracks for Intakes Design of Small Dams Fundamentals of Irrigation Engineering Nem Chand & Bros. Roorkee (1983) Handbook of Hydroelectric Engineering (Second edition) .. pages 357 to 365 Nem Chand & Bros. Roorkee (1985) 1. 1. 11 Other References Bucher and Krumdieck Guidelines for the Design of Intake Structures for Small Hydro Schemes Hydro 88/3rd transnational Conference on Small Hydro, Cancun Mexico. Bouvard, M. Mobile Barrages and Intakes on Sedime nt Transporting AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 20118 Razvan, E. 1. 2. Rivers IAHR Monograph, A. A. Balkema Rotterdam (1992) River Intakes and Diversion DamsElsevier, capital of The Netherlands (1988) SEMI PERMANENT HEADWORKS (MINI HYDRO) For mini hydro projects the need to minimize capital cost of the head works is of prime importance. This issue poses the greatest challenge where the head works have to be constructed on alluvial foundations. This challenge is addressed by adoption of less rigorous standards and the application of simplified designs adapted to the skills available in remote areas. A typical layout is shown in Figure 2. 2. 3. 1. 2. 1 Design Parameters Hydraulic design should be based on the following design criteria Plant flow Qp) = QT + QD Where QT = total turbine flow (m3/s) QD = desilter flushing flow (= 0. 20 QT) m3/s QFC = feeder canal flow (= 1. 20 QT) m3/s QF = gravel flushing flow (= 2. 0 QP) Spillway design flow (SDF) = Q10 Where Q10 = flood peak flow with ten year return period. 1. 2. 2 Layout ? To be reviewed Intake approach velocity = 1. 0 m/s Regulator gate W/H = 2 Flushing channel depth (HD) = 2H + W/3 Flushing channel minimum width = 1. 0 m Assumed flushing gate W/H = 2, determine H from orifice equation, as below Q f = 0. 53? 2 H 2 . 2 gY1 Y1 = HD for design condition Where W width of gate (m) H = height of gate (m) Yi = upstream depth (m) = depth of flushing channel (m) HD Select the next largest manufactures standard gate size above the cypher dimensions. 1. 2. 3 Weir AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 20119 Determine weir height to suit intake gate and flushing gate dimensions, as shown in Figure 2. 2. 3. For weirs founded on permeable foundations the necessary structure duration to control failure by yell should be determined in accordance with Section 2. 2. 1/4. 1 of this Standard.A stepped arra ngement is recommended for the downstream face of the weir to dissipate hydraulic energy. The height of the steps should not exceed 0. 5 m and the rise over run ratio should not less than 1/3, the stability of the weir bollocks up-section design should be canvass for flotation, over turning and sliding in accordance with Section 2. 3. 1. 1. 3 TRENCH INTAKES Trench intakes are intake structures located in the river bed that draw off flow through racks into a intrench which conveys the flow into the project water conductor system. A characteristic of trench intakes is that they have minimum impact on river levels.Trench intakes are applied in situations where traditional headwork designs would be excessively expensive or result in objectionable rises in river levels. There are two quite different applications on wide rivers and on mountainous streams, but the basic equations are the same for both types. The trench intake should be located in the main river channel and be of suffic ient width to collect the design project flow including all flushing flows. If the length of the trench is less than the width of the river, cut off walls will be required into each bank to pr fact the river from bypassing the structure.Trench weirs function best on weirs with slopes greater than 4%-5%, for blandish slopes diversion weirs should be considered. The spacing between racks is selected to prevent entry of bed load into the trench. The following terms are some clock used in referring to trench intake designs. Trench weir, when the trench is installed in a raised embankment. Tyrolean or Caucasian intakes, when referring to trench intakes on mountainous streams. Features AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201110 1. 3. 2 Design ParametersThe following design parameters are suggested for the dimensioning of trench weirs. Design Flows The following design flows are recommended Bedload flushing flow (from collect or box) = 0. 2 QT Desilter flushing flow = 0. 2 QT Turbine flow = 1. 0 QT Total design flow = 1. 4 QT Dimensional Layout AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201111 The following factors should be considered in determining the principal dimensions length, breadth and depth of a trench weir Minimum width (B)= 1. 25 m (to facilitate manual cleaning) Length should be compatible with river cross section. It is recommended that the trench be located across main river channel. Maximum width (B) ? 2. 50m. Trashrack bars longer than about 2. 50 m may require support as slenderness ratios become excessive. Invert of collector box should be kept a high as possible. Racks The clear spacing between bars should be selected to prevent entry of bed-load particles that are too large to be conveniently handled by the flushing system. Generally designs are based on excluding particles greater than medium gravel size from (2 cm to 4 cm).A clear opening of 3. 0 cm is recommended for design. A slope across the rack should be provided to avoid accumulation of bed load on the racks. Slopes normally used vary from 0 to 20. Rectangular bars are recommended. Bar structural dimension shall be designed in accordance with Section 2. 2. 1/5. 0 of this Standard. An grant contraction coefficient should be selected as explained in the following sub-section. Assume 30% blockage. Spacing between racks is designed to prevent the entry of bedload but must in like manner be strong enough to support superimposed loads from bedload accumulation, men and equipment.This issue is discussed further in Subsection 2. 2. 3 / 2. 0. 1. 3. 3 Hydraulic Design of Trench Intake The first step in hydraulic design is to decide the width of the trench intake bearing in mind the flow capacity required and the bathymetry of the river bed. The next step in hydraulic design is to determine the minimum trench breadth (B) that will capture the requ ired design flow. The design approach assumes complete capture of river flow, which implies, that river flow is equal to plant flow for the design condition. Hydraulic design is based on the following assumptions Constant specific energy across racks. Effective head on screen is equal to base pressure (depth) Approach velocity is subcritical with a critical section at the entry to the structure as shown in figure 2. 2. 3/1. The set of equations proposed is based on the method inclined by Lauterjung et al (1989). First calculate y1 AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201112 2 y 1 = k. H0 3 (1) Where y1 = depth at upstream edge of rack Ho = the energy head of the approaching flow k = an adjustment factor (m) m) (-) k is a function of inclination of the rack and can be determined from the following table Values of k as a Function of Rack Slope (? ) Table 2. 2. 1/1 ? = 0 2 4 6 8 10 12 k = 1. 000 0. 980 0. 961 0. 944 0. 927 0. 910 0. 894 ? = 14 16 18 20 22 24 26 k = 0. 879 0. 865 0. 851 0. 837 0. 852 0. 812 0. 800 Then calculate the breadth of the collector trench from the following equations (2) to (4) 1. 50 q (2) L= E1. E 2 C. cos? 3/2 . 2gy 1 Where L = sloped length across collector trench (m) E1 = blockage factor E2 = Effective screen area = e/mC = contraction coefficient ? = slope of rack in degrees y1 = flow depth upstream from Equation 1. (m) q = unit flow entering intake (m3/s per m) e = clear distance between bars (cm or m) m = c/c spacing of bars (cm or m) Assume E1 = 0. 3 (30%) blockage. C can be calculated from the following formula (as reported by Raudkivi) Rectangular bars ?e? C = 0. 66 ? ? ?m? ?0. 16 ?m? .? ? ?h? 0. 13 Assume h = 0. 5 y1. This formula is valid for 3. 5 (3) h e 0. 2 and 0. 15 0. 30 m m Finally, the required breadth (B) can be determined as below B = L cos ? -(4) AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydra ulic Design Of Small Hydro Plants /May 201113 1. 3. 4 Hydraulic Design of Collector Trench Normally a sufficient slope on the invert of the trench is provided to ensure efficient flushing of bed-load particles that would otherwise accumulate on the invert of the trench. A suitable scouring slope can be estimated from the following equation Ss = 0. 66 d 9 / 7 6/7 qo Where d = sediment size (m) qo = flow per unit width (Q/B) at outlet of trench (m3/s per m) Ss = design slope of trench invert.The minimum depth of the trench at the upstream and is normally between 1. 0m to 1. 5 m, based on water depth plus a freeboard of 0. 3 m. For final design the flow indite should be computed for the design slope and the trench bottom profile confirmed or adjusted, as required. A step-by-step procedure for calculating the flow profile that is applicable to this problem can be found in Example 124, page 342-345 of Open-Channel Hydraulics by Ven. T. Chow (1959). In most cases the profile will be sub critical with control from the downstream (exit) end.A suitable starting point would be to assume critical flow depth at the exit of the trench. 1. 3. 5 Collector Chamber The trench terminates in a collector box. The accrual box has two outlets, an intake to the water conductor system and a flushing pipe. The flushing pipe must be design with the capacity to flush the bed-load sediment entering from the trench, while the project flow is withdrawn via the intake. The bottom of the collection box must be designed to provide adequate ducking for the flushing pipe and intake to suppress undesirable vortices.The flushing pipe should be lower than the intake and the flushing pipe sized to handle the discharge of bed load. If the flushing pipe invert is below the outlet of the trench, the Engineer should consider steepening the trench invert. If the trench outlet invert is below the flushing pipe invert, the latter should be lowered to the elevation of the trench outlet or below. The dec k of the collector box should be located above the design flood level to provide safe access to operate gates. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201114 1. 3. Flushing thermionic tube The flushing pipe should be designed to provide a high enough velocity to entrain bed-load captured by the weir. A velocity of at least(prenominal) 3. 0 m/s should be provided. If possible, the outlet end of the pipe should be located a minimum of 1. 0m above the river bed level to provide energy to keep the outlet area free from accumulation of bed load that could block the pipeline. 1. 3. 7 References on Trench weirs CBIP, (2001) Manual on Planning and Design of Small Hydroelectric Scheme Lauterjung et al (1989) Planning of Intake Structures Freidrich Vieweg and Sohn, Braunswchweig GermanyIAHR (1993) Hydraulic Structures Design Manual Sedimentation Exclusion and Removal of Sediment from Diverted Water. By Arved J. Raudkivi Publisher Tay lor & Francis, New York. Chow (1959) Open- Channel Hydraulics Publisher McGraw-Hill Book Company, New York. 1. 4 RESERVOIR, CANAL AND PENSTOCK INTAKES The designs of reservoir, canal and penstock intakes are all based on the same principles. However, there are significant interlingual renditions depending on whether an intake is at the forebay reservoir of a run-of-river plant or at entrepot reservoir with large draw down or is for a power tunnel, etc.Examples of a variety of layouts can be fond in IS 9761 Hydropower Intakes Criteria for Hydraulic Design or Guidelines for Design of Intakes for Hydropower Plants (ASCE, 1995). The features common to all designs are shown in the following sketch AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201115 The objectives of good design are To prevent entry of floating debris. To avoid formation of air entraining vortices. To minimize hydraulic losses. 1. 4. 1 Control of floating debrisTo prevent the entry of debris a trashrack is placed at the entry to the intake. For small hydro plants the trashrack overall size is determined based on an approach velocity of 0. 75 m/s to 1. 0m/s to facilitate manual raking. Trashracks may be designed in panels that can be lowered into place in grooves provided in the intake walls or permanently attacked to anchors in the intake face. The trashracks should to sloped at 14 from the vertical (4V1H) to facilitate raking. The spacing between bars is determined as a function of the spacing between turbine runner blades.IS 11388 Recommendations for Design of Trashracks for Intakes should be consulted for information about spacing between trashracks bars, structural design and vibration problems. Also, see Section 2. 2. 1/5 of this Standard. 1. 4. 2 Control of Vortices First of all the direction of approach velocity should be axial with respect the intake if at all possible. If flow approaches at a significant angle (greater than 45o) AHEC /MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201116 from axial these will be significant risk of vortex problems.In such a situation an experienced hydraulic engineer should be consulted and for important projects hydraulic model studies may be required. For normal approach flow the submergence can be determined from the following formulae S = 0. 725VD0. 5 S D V = submergence to the roof of the gate section (m) = diameter of penstock and height of gate (m) = velocity at gate for design flow. (m/s) Where A recent paper by Raghavan and Ramachandran discusses the merits of various formulae for determining submergence (S). 1. 4. 3 Minimization of Head lossesHead losses are minimized by providing a streamlined transition between the entry section and gate section. Minimum losses will be produced when a streamlined bellmouth intake is used. For a bellmouth intake the transition section is formed with quadrants of ellipses as shown in the fol lowing sketch. The bellmouth type intake is preferred when ever the additional costs are economically justified. For smaller, mainly mini hydropower stations, simpler designs are often optimal as the cost of construction of curved cover surfaces may not be offset by the value of lessening in head losses.Details on the geometry of both types are given Bellmouth Intake Geometry Geometries for typical run-of-river intakes are shown below A gate width to height of 0. 785 (D) 1. 00 (H) with H = D is recommended. This permits some reduction in the cost of gates without a significant sacrifice in hydraulic efficiency. There is a second transition between the gate and penstock, rectangular to circular. For a gate having H = D and W= 0. 785D the flow velocity at the gate will be equal to the velocity in the penstock so no further flow acceleration is produced in this section. A length for this transition of 1. x D should be satisfactory. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201117 The head loss co-efficient for this arrangement in Ki =0. 10 Details for layout of bell mouth transitions connecting to a slant penstock are given in IS9761. Simplified layout (Mini-Hydro) For smaller/mini hydro projects intake design can be simplified by forming the transition in plane surfaces as shown below The head loss for this design (Ki) = 0. 19V2/2g. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201118 . 4. 4. AIR transmit An air vent should be placed downstream of the head gate to facilitate air exchange between atmosphere and the penstock for the following conditions sluice filling when air will be expelled from the penstock as water enters. Penstock draining when air will enter the penstock to occupy the outer space previously filled by water. The air vent (pipe) must have an adequate cross section area to effectively handle these exchanges of air. The following design rules are recommended Air vent area should the greater of the following values Where (m3/s) AV = 0. 0 Ap or QT AV = 25. 0 (m2) AV = cross-section area of air vent pipe AP = cross-section area of penstock (m2) QP = turbine rated flow ( ? QT of more than one turbine on the penstock) The air vent should exhaust to a safe location unoccupied by power company employees on the general public. 1. 4. 5 PENSTOCK FILLING A penstock should be filled late to avoid excessive and dangerous blowback. The recommended practice is to control filling rate via the head gate. The AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201119 ead gate should not be opened more than 50 mm until the penstock is completely full. (This is sometime referred to as cracking the gate. ) 1. 4. 6 REFERENCES ON PENSTOCK INTAKES 1. 4. 7 Indian Standard Cited. IS 9761 Hydropower Intakes Criteria for Hydraulic Design OTHER REFERENCES Guidelines for Design of Intakes for Hydroelectric Plants ASCE, New York (1995) Validating the Design of an Intake Structure By Narasimham Raghavan and M. K. Ramachandran, HRW September 2007. seculars Guidebook European Small Hydro Association Brussels, Belgium (June 1998)Available on the internet. Vortices at Intakes By J. L. Gordon Water Power & Dam Construction April 1970 1. 5. TRASHRACKS AND gumshoe RACKS 1. 5. 1 Trashracks Trashracks at penstock intakes for small hydro plants should be sloped at 4 V 1H to facilitate manual raking and the approach velocity to the trashracks limited to 1. 0 m/s or less. Use of rectangular bars is normal practice for SHPs. Support beams should be alignment with the flow direction to minimize hydraulic losses. expatiate trashrack design should be done in accordance with IS 11388. 1. 5. 2Safety Racks Safety racks are required at tunnel and upside-down siphon entries to prevent animals or people who may have fallen into the canal from being pulled into these submerged water ways. A clear spacing of 200 mm between bars is recommended. Other aspects of design should be in accordance with IS 11388. 1. 5. 3 References on Trashracks IS11388 Recommendations for Design of Trashracks for Intakes. ASCE (1995) Guidelines for Design of Intakes for Hydroelectric Plants. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201120 DRAWINGSAHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201121 AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201122 2. HYDRAULIC DESIGN OF WATERWAYS The waterways or water conduction system is the system of canals, aqueducts, tunnels, inverted siphons and pipelines connecting the head works with the forebay tank. This Section provides guidelines and norms for the hydraulic design of these structures. 2. 1 2. 1. 1 CANALS Canals for small hydro plants are typically constructed in masonry or reinforc ed concrete.Several typical cross section designs are shown below AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201123 Lined canals in earth, if required, should be designed in accordance with Indian Standard IS 10430. A further constituent of canal types is based on function Feeder canal to connect the head regulator (intake) to the desilter Power canal to connect the desilter to the Forebay tank. 2. 1. 2 Feeder Canals 2. 1. 2. 1 Feeder canal hydraulic design shall be based on the following criteria = Turbine flow (QT) + Desilter flushing flow (QF).Design flow (Qd) AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201124 2. 1. 2. 2 Scouring velocity A sufficiently high velocity must be provided to prevent deposition of sediment within the canal. This (scouring) velocity can be determined from the following formulae d 9/7 S C = 0. 66 6 / 7 n = 0. 015 q 1 1 ? VS = . R 2 / 3 . S C/ 2 n Where Sc = Scouring slope d = Target sediment size (m) q = Flow per unit width (Q/W) (m/s/m) R = hydraulic radius (m) Vs = scouring velocity (m/s) n = Mannings roughness coefficient 2. 1. 2. 3 optimisationThe optimum cross section dimensions, slope and velocity should be determined by economic analysis so as to minimize the total feeling time costs of capital, O&M and head losses (as capitalized value). The economic parameters for this analysis should be chosen in consultation with the becharm regional, state or central power authorities these parameters include Discount rate (i) Escalation rate(e) Plant load factor Service life in years (n) Annual O+M for canal (% of capital cost) Value of energy losses (Rs/kWh). Also see Section 1. 7 of this Standard. The selected design would be based on the highest of Vs or Voptimum. . 1. 2. 4 Freeboard A freeboard allowance above the steady state design water level is required to contain water safely within the canal in event of pow er outages or floods. A minimum of 0. 5 m is recommended. 2. 1. 3 Power Canals Power canal design shall be based on the following criteria a) Design flow = total turbine flow (QT) b) Power canal design should be based on optimization of dimensions, slope and velocity, as explained in the previous section. For mini-hydro plants Q 2. 0 m3/s optimal geometric design dimensions for Type 1 (masonry construction) can be estimated by assuming a longitudinal slope of 0. 04 and a Mannings n value of 0. 018. Masonry construction would normally be preferred for canals with widths (W) less than 2. 0 m (flow area = AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201125 2. 0 m2). For larger canals with flow areas greater than 2. 0m2, a Type 3, box culvert design would be preferred based on economic analysis. c) Freeboard A freeboard allowance above the steady state design level is required to contain water safety within the canal in event of powe r outages. The waterway in most SHPs terminates in a Forebay tank.This tank is normally equipped with an outflow weir to discharge surplus water or an escape weir is provided near to the forebay tank. For mini-hydro plants a minimum freeboard of 0. 50 m is recommended. The adequacy of the above minimum freeboard should be verified for the following conditions Maximum flow in the power canal co-incident with sudden outage of the plant. Design flow plus margins for leakage losses (+0. 02 to +0. 05 QT) and above rated operation (+ 0. 1QT). Characteristics of head regulator flow control. The freeboard allowance may be reduced to 0. 5 m after taking these factors into consideration. The maximum water level occurring in the forebay tank can be determined from the weir equation governing flow in the escape weir. 2. 1. 4 Rejection Surge Designs which do not incorporate downstream escape weirs would be subject to the occurrence of a rejection surge in the canal on sudden turbine shutdown , giving above static water levels at the downstream end, diminution to the static level at the upstream (entry) end of the water way. Methods for evaluating water level changes due to a rejection surge are explained in Section 2. 2. 2 / 7. 0 of this Standard. . 2 AQUEDUCTS Aqueducts are typically required where feeder or power canals pass over a gully or side stream valley. If the length of the aqueduct is relatively short the same channel dimensions as for the canal can be retained and there would be no change in hydraulic design. For longer aqueducts design would be based on economic analysis subject to the proviso that flow remains sub critical with NF ? 0. 8 in the flume sections. The following sketch shows the principal dimension of aqueduct entry and exit transitions and flume section. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design OfSmall Hydro Plants /May 201126 The changes in invert elevation across the entry and exit structures can be calculated b y Bernoulis equation as below Entry transition consider cross section (1) and (2) V2 V2 Z 1 + D + 1 = Z 2 + d + 2 + hL 2g 2g and 2 b? V ? hL = 0. 10 ? 1 ? ?. 2 ? B ? 2g Z2 can be determined from the above equations, since all geometrical parameters are known. Flume Sections (2) to (3) The slope of the flume section is determined from Mannings equation 2 ? Vn ? ( S ) = ? 2 / 3 ? . A Mannings n = 0. 018 is suggested for concrete channels. ?R ?Some designers increase this slope by 10% to provide a margin of safety on flow capacity of the flume. Exit transition consider cross section (3) and (4) V2 V2 Z 3 + d + 3 = Z 4 + D + 4 + hL 2g 2g AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201127 and 2 b? V ? hL = 0. 20 ? 1 ? ?. 3 ? B ? 2g Z4 can be determined from the above equations, since all geometrical parameters are known. The same basic geometry can be adapted for transition between trapezoidal canals sections and rectangular flu me section, using consider flow width (B) = A/D. . 3. INVERTED SYPHONS 2. 3. 1 Inverted syphons are used where it is more economical to route the waterway underneath an obstacle. The inverted syphon is made up of the following components Entry structure Syphon barrels Exit structure Entry Structure Hydraulic design of the entry structure is similar to the design of reservoir, canal and penstock intakes. Follow the guidelines given in Section 2. 2. 2/2. of this Standard. Syphon barrels The syphon barrel dimensions are normally determined by optimization ? V? ? does not tudies, with the proviso that the Froude Number ? N F = ? gd ? ? ? exceed 0. 8. Invert elevations are determined by accounting for head losses from entry to exit of the structure using Bernoulis equation. For reinforced concrete channels a Mannings n value of 0. 018 is recommended. The head loss coefficients for mitre bends can be determined from USACE HDC 228. 2. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201128 AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201129 Exit structure The exit structure is designed as a diverging transition to minimize head losses the design is similar to the outlet transition from flume to canal as discussed in Subsection 2. 2. 2/2 of this Standard. The following sketches show the layout of a typical inverted siphon. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201130 2. 3. 2 Reference on Aqueducts and Inverted Syphons Hydraulic Structures By C. D. Smith University of Saskatchewan Saskatoon (SK) Canada 2. 4. LOW PRESSURE PIPELINESLow pressure pipelines may be employed as an alternative to pressurized box culverts, aqueducts or inverted syphons. Concrete, plastic and nerve pipes are suitable depending on site conditions and economics. Steel pipe is often an attractive alternative in place of concrete aquedu cts in the form of pipe bridges, since relatively large diameter pipe possesses significant inherent structural strength. Steel pipe (with stiffening rings, as necessary), concrete and plastic pipe also have significant resistance against external pressure, if buried, and offer alternatives to inverted syphons of reinforced concrete construction.Generally pressurized flow is preferred. The pipe profile should be chosen so that pressure is positive through out. If there is a high point in the line that could trap air on filling an air bleeder valve should be provided. Otherwise, hydraulic design for low pressure pipelines is similar to the requirements for inverted syphons. The choice of type of design low pressure pipeline land pipeline material), inverted syphon or aqueduct, depends on economic and constructability considerations, in the context of a given SHP. Mannings n Values for selected Pipe Materials Material Welded Steel polythene (HDPE) Poly Vinyl Chloride (PVC)Asbestos Cem ent Cast iron Ductile iron Precast concrete pipe Mannings n 0. 012 0. 009 0. 009 0. 011 0. 014 0. 015 0. 013(2) Note (1) From Table 5. 4 Laymans Guide Book ESHA (2) From Ven T. Chow Open Channel Hydraulics AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201131 2. 5. TUNNELS 2. 5. 1 Tunnels often provide an appropriate solution for water conveyance in mountainous areas. Tunnels for SHP are generally of two types. Unlined tunnels Concrete lined tunnels On SHP tunnels are usually used as part of the water ways system and not subject to high pressures. . 5. 2 Unlined tunnels Unlined water tunnels can be used in areas of favourable geology where the following criteria are satisfied a) Rock mass is adequately water tight. Rock surfaces are sound and not vulnerable to erosion (or erodible zones b) are suitably protected. The static water pressure does not exceed the magnitude of the minor field c) rock stress. Controlled security deposi t blasting is recommended in order to minimize over break and produce sound rock surfaces. Additionally, this construction approach tends to produce relatively uniform surfaces and minimizes the hydraulic roughness of the completed tunnel surfaces.Design velocities of 1. 5 to 2. 0 m/s on the mean AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201132 cross section area give optimal cross section design. It is normal practice to provide a 100mm thick reinforced concrete pavement over leveled and compacted tunnel muck in the invent of the tunnel. IS 4880 Part 3 provides additional guidance on the hydraulic design of tunnels and on the excerption of appropriate Mannings n values. 2. 5. 3 Lined Tunnels Where geological are unfavourable it is often necessary to provide concrete linings for support of rock surfaces.IS4880 split 1-7 give comprehensive guidelines on the design of lined tunnels. 2. 5. 4 High Pressure Tunnels Design of high p ressure tunnels is not covered in this standard. For high pressure design, if required, the designer should consult an experienced geotechnical engineer or engineering geologist. For the purpose of this standard, high pressure design is defined as tunnels subject to water pressures in excess of 10m relative to the crown of the tunnels. 2. 5. 5 Reference on Tunnels IS Standards IS 4880 Code of Practice for the Design of Tunnels Conveying Water. Other References Norwegian Hydropower Tunnelling (Third volume of collected papers) Norwegian Tunneling Society Trondheim, Norway. www. tunnel. no Notably Development of Unlined Pressure Shafts and Tunnels in Norway, by Einar Broch. 2. 6. CULVERTS AND CROSS-DRAINAGE WORKS Small hydro projects constructed in hilly areas usually include a lengthy power canal routed along a hillside contour. Lateral inflows from streams and gullies intercepted by SHP canals often transport large sediments loads which must be prevented from entering the canal. The first line of defense is the canal upstream ditch which intercepts local lateral runoff.The flow in these chains must be sporadically discharged or the drain capacity will be exceeded. Flow from these drains is usually evacuated via culverts passing underneath the canal. These culverts would normally be located where gullies or streams cross the canal alignment. The capacity of canal ditches should be decided taking into consideration the average distance between culverts. In the rare cases when distance between culverts is excessive, consideration should be given to diverting AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201133 itch flows across the canal in flumes or half round pipes to discharge over the downhill side of the canal at suitable locations. Culverts are usually required where the canal route crosses gullies or streams. Culverts at these points provide for flow separation between lateral inflows and canal inflows an d often present the most economical solution for crossing small but steep valley locations. It is recommended that culverts design be based on the following hydrological criteria. For mini hydro projects, 1 in 10 year flood (Q10) For small hydro projects, 1 in 25 year flood (Q25)Where it is practical to extract the necessary basin parameters, the procedures given in Section 1. 4 should be applied. Otherwise design flows should be estimated from field measurements of cross section area and longitudinal slope at representative cross section of the gully or side stream. A survivable design approach is further recommended with canal walls strengthened to allow local over topping without damage to the canal integrity when floods exceed the design flood values. Detailed hydraulic design should be based on information from reliable texts or design guidelines such as Design of Small Bridges and Culverts Goverdhanlal 2. 7 2. 7. 1 Engineering and Design Drainage and Erosion Control. Eng ineering Manual EM 1110-3-136 U. S. Army Corps of Engineers (1984) www. usace. army. mil/publications/eng-manuals Manufacturers guides, notably American Concrete Pipe Association www. concrete-pipe. org Corrugated Steel Pipe Institute www. cspi. ca Power Canal Surges Power canals that are not provided with escape weirs near their downstream end will be subject to canal surges on rapid load rejections or load additions.The rejection surge will typically cause the downstream water level to rise above static level and may control the design of canal freeboard. For load additions there is a risk that the level will fall to critical at the downstream end and restrict the rate at which load can be taken on by the unit. The following formulae taken from IS 7916 1992 can be used to estimate the magnitude of canal surges. AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201134 Maximum surge height in a power channel due to load rejection may be calculated from the empiric formulae given belowFor abrupt closure hmax = K 2 + 2 Kh For gradual closure within the period required for the first wave to incite twice the length of the channel K hmax = + V . h / g 2 Where hmax = maximum surge wave height, K = V2/2g = velocity head, V = mean velocity of flow, and area of cross sec tion h = effective depth = top width Maximum water level resulting from a rejection surge at the downstream of a canal Maximum W. L. = Yo + hmax Minimum water level resulting from by a start up surge at the downstream end of a canal Minimum W. L. = YS hmax Where Yo YS = steady state downstream water level static downstream water level. The maximum water level profile can be approximated by a straight line joining the maximum downstream water level to the reservoir level. 2. 7. 2 Canal Surges on Complex Waterways For waterway systems comprising several different water conductor types, the above equations are not applicable. In such cases a more deta iled type of analysis will be required. The U. S. National Weather Service FLDWAV computer program can be used to solved for the transient flow conditions in such cases (Helwig, 2002). 2. 7. 3 References IS Standards citedIS 7916 1992 Open Channel Code of Practice. Other References Application of FLDWAV(Floodwave) Computer Model to Solve for Power Canal Rejection Wave for saucer-eyed and Complex Cases. P. C. Helwig Canadian Society for Civil Engineering Proceedings, Annual Conference Montreal, Canada (2002). AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201135 3. HYDRAULIC DESIGN OF DESILTERS 3. 1 BACKGROUND Sediment transported in the flow, especially particles of hard materials such as quartz, can be harmful to turbine components.The severity of damage to equipment is a function of several variables, notably sediment size, sediment hardness, particle shape, sediment denseness and plant head. The control of turbine wear problems due to silt erosion requires a comprehensive design approach in which sediment properties, turbine mechanical and hydraulic design, material selection and features to facilitate equipment maintenance are all considered (Naidu, 2004). Accordingly the design parameters for desilter design should be made in consultation with the mechanical designers and turbine manufacturer.Where the risk of damage is judged to be high a settling basin (or desilter) should be constructed in the plant waterway to remove particles, greater than a selected target size. 3. 1. 1 Need The first design decision is to determine whether the sediment load in the river of interest is sufficiently high to merit construction of a desilter. There is little guidance available on this topic however, the following limits are suggested by Naidu (2004) Table 2. 2. 3/1. 0 Concentration Suggested Maximum Allowable Sediment versus Plant Head. Parameter Head Maximum allowable sediment concentrationLow and Medium Head Turbin es ? 150 m High Head Turbines 150 m 200 ppm 150 ppm 3. 1. 2 Removal Size There are also large divergences of opinion on the selection of design size for sediment removal. Nozaki (1985) suggests a size range of between 0. 3 mm to 0. 6 mm for plant heads ranging from 100 m to 300 m. Indian practice is to design for a particles size of 0. 20 m regardless of head. Some authors suggest that removal of particles smaller than 0. 20 mm is not practical. The adoption of 0. 20 mm is the design (target) sediment size is recommended for Indian SHP designs.AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201136 3. 1. 3 Types of Desilters There are two basic types of desilters Continuous flushing type Intermittent flushing type Guidelines for design of both types are given in this section. 3. 2. DESIGN CONSIDERATIONS 3. 2. 1 Data Requirements (Small Hydro Plants) It is recommended that a program of suspended sediment sampling be initiated near the intake site from an early stage during site investigations to ensure that sufficient data is available for design.The sampling program should extend through the entire rainy season and should comprise at least two readings daily. On glacier fed rivers where diurnal flow variations may exist, the schedule of sampling should be adjusted to take this phenomenon into account and the scheduled sampling times be adjusted to coincide with the hour of peak daily flow with another sample taken about twelve hours later. While it is often assumed that sediment load is directly related to flow, this is only true on the average, in a statistical sense.In fact it is quite likely, that the peak sediment event of a year may be associated with a unique upstream event such as a major landslide into the river. Such events often account for a disproportionately large proportion of the annual sediment flow. Therefore, it would also be desirable to design the sediment measurement program to provide more detailed information about such events, basically to increase the sampling frequency to one sample per 1 or 2 hours at these times. A five year long sediment collecting program would be ideal. Less than one monsoon season of data is considered unsatisfactory.Some authors suggest that the vertical variation of sediment concentration and variations horizontally across the river be measured. However, on fast flowing rivers inherent turbulence should ensure uniform mixing and sampling at one representative point should be sufficient. The data collected in a sediment sampling program should include Mean daily concentration of suspended sediment (average of two readings twelve hours apart) Water temperature Flow (from a related flow gauging program) The following additional information can then be derived from collected samples.AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201137 A sediment rating curve (sediment concentration versu s flow where possible) pinch size gradation curve on combined sample Specific gravity of particles. It is also recommended that a petrographic analysis be carried out to identify the component minerals of the sediment mix. It is likewise recommended that experiments be made on selected ranges of particles sizes to determine settling velocities. A further discussion on the subject of sediment sampling is given in Avery (1989)The characteristics of the sediment on a given river as obtained from a data collection program will assist in selection of appropriate design criteria. 3. 2. 2 Data Requirements (Mini Hydro Plants) On mini hydro projects where resources and time may not be available to undertake a comprehensive sampling program, selection of design parameters will depend to a great extent on engineering judgment, supplemented by observations on site and local information. The following regional formula by Garde and Kothyari (1985) can be used to support engineering decision ma king. 0. 19 ?P ? 0 Vs = 530. 0 P0. 6. Fe1. . S0. 25 Dd . 10 .? max ? ?P? Where Vs = mean sediment load in (tonnes/km2/year) s = average slope (m/m) Dd = drainage density, as total length of streams divided by catchment area (km/km2) P = mean annual precipitation (cm) Pmax = average precipitation for wettest month (cm) Fe = ground cover factor, as below 1 Fe = 0. 80 AA + 0. 60 AG + 0. 30 AF + 0. 10 AW ? Ai = arable land area AA = grass land area (all in km2) AG AF = forested area AW = louse up land area (bare rock) 3. 2. 3 Design Criteria The principle design criteria are 1. The target size for removal (d) d = 0. 20 mm is recommended 2.Flushing flow QF = 0. 2 QP is recommended 3. Total (design) flow QT = QP + QF = 1. 2 QP. Where QP is plant flow capacity in (m3/s). AHEC/MNRE/SHP Standards/ Civil Works Guidelines For Hydraulic Design Of Small Hydro Plants /May 201138 3. 2. 4 Siting The following factors control site selection 1. A site along the water way of appropriate size and re latively level with respect to cross section topography 2. A site high enough above river level to provide adequate head for flushing. For preliminary layout a reference river level corresponding to the mean annual flood and minimum flushing head of 1. 0 m is recommended. In principle a desilting tank can be located anywhere along the water conductor system, upstream of the penstock intake. Sometimes it is convenient to locate the desilting basin at the downstream end of the waterway system where the desilter can also provide the functions of a forebay tank. However, a location as close to the head works is normally preferred, site topography permitting. 3. 3 Hydraulic Design A desilter is made up of the following elements Inlet section Settling tank Outlet section Flushing system 3. 3. 1

Dubai: Globalization on Steroids Essay

Promotions for Dubai on CNN, BBC World, and other satellite channels show a shimmering skyline of glass and steel slip towers with their graceful curves and aquiline shapes, suggesting a distant galaxy where all the unpleasantness of urban life has been airbrushed away. But advertising almost always offers much than promise than reality, whether the product is potato chips or a city or a country. Seen through the lens of the everyday, nothing in this city is so clear. Its hard to come to terms with Dubai, be piss there is confusion even in the way it is draw by the media. It is often referred to as a Persian Gulf country (which it definitely isnt), or a city-state (wrong again), or a Gulf emirate (also not accurate, because Dubai, the city, is only part of Dubai, the emirate, which is an integral part of the United Arab Emirates). But angiotensin converting enzyme thing is clear during the trio years Ive lived here, it has undergone the kind of transformation that a city might experience once in a lifetime.Each time I snuff it my apart ment block, I drive past shells of unfinished buildings with piles of sand and rubble spilling onto the sidewalks, and Im struck by other irony of Dubai that the more the city aspires to be the premier megalopolis of the 21st century, the more it resembles 1945 Dresden. The pace of growth has left many residents wondering what the hurry is. Yet everyone seems to be in a rush. On fashion plate Zayed Road, the 12 lanes linking Dubai with Abu Dhabi, the UAE capital 100 miles to the south, drivers barrel down the fast lanes at 90 miles an hour. Late on a Friday night, drivers weave in and out of the speeding traffic, which results in an appalling accident rate that leaves crushed fenders and tangles of gnarled metal piled along the roadsides.Has any place on earth self-aggrandising as quickly or been transformed so completely? Aerial photos from the early 1960s show a dusty, ramshackle trading post enclose be-tween the Pe rsian Gulf and the Creek, Dubais inland waterway and outlet to the sea. Ten years later it was beginning to take on the look of a golden city a decade after that it had changed so much as to be almost unrecognizable. The one-runway airstrip had been replaced by an international airport, a forest of office towers had grown up along the Creek, and residential tracts had spread across barren expanses of desert that stretched to the horizon.Dubai today is often described as a Wild westerly town, and the widespread economic opportunism lends some truth to the description. Driving the expansion is neither natural resources nor old-world industrialization but rather the gears of a 21st-century scrimpingbanking, technology, trade and tourism, real estate, and media outlets. The tycoons cutting business deals in hotel restaurants and on beach-club patios are representatives of this new global economyTaiwanese bankers and Lebanese import/exporters, Russian oligarchs and Iranian property in vestors. But even Dubai is not immune from the vicissitudes of global economicsthe September worldwide monetary crisis drained almost $6 billion from its financial markets. In spite of its rapid growth and the influence of globalization on Dubai, a bit of the old city can allay be found. bye through the contended market on the Deira side of the Creek, past spice vendors displaying their wares in 100-pound sacks then go up winding, narrow lanes past the gold, silver, and tex cover dealers from Pakistan and Iran and the Indian merchants who speak fluent Arabic, their roots in Dubai reaching tolerate generations.From there it is only a short walk up to the Al-Hamadiya School, now a museum, the introductory place to offer formal education in Dubai. Exhaust-spewing water taxis still shuttle commuters across the Creek between the twisting roads of Deira and the traditional Bastakia quarter, home to the pre-oil formulas palace, a covered market, and the site of a former fort. On th e Deira side, ships unload pallets of cargo, just as they have ever since Dubai served as a comfortable transit point for much of the trade that passed between India and Africa and the rest of the Arabian peninsula. In the neighbourhoods of Jumeirah and Umm Suqeim, quiet side streets lined with white houses topped with red tile roofs glisten in the afternoon sun, suggesting the placid tranquillity of southern California when southern California was tranquil and placid. Early in the morning, Indonesian housemaids sweep driveways with modify palm branches, and South Asian labourers still use these primitive implements to clear the paths in the local parks. It is hard to reconcile such images with those more popularly associated with Dubai. in that location is the Royal Mirage Hotel, whose silent, soaring hallways and courtyards have been designed in palatial Arabian splendour. Not far away is the Madinat Jumeirah, some other hotel complex and an adjoining shopping arcade, where th e chink music of the oud is pumped into the elevators and down the narrow, serpentine corridors in an effort to re-create the sensual mysticism of the Arabian covered market. But here, too, like almost everywhere in Dubai, the traditional clashes with the modernistic, and the uneasy blend is meant to serve consumerism at the Madinat Jumeirah, res-taurants and cafs surround artificial lakes, gift boutiques cater to upscale travellers, and live music echoes from the JamBase, one of Dubais hot spots. All of the glitz has made Dubai trendy among the globetrotting business set and holidaymakers interested in a taste of the Middle Eastas long as it is tempered with a hefty dose of Club Med but the changing character of the city is not endorsed by everyone.Among so-called locals, or Emirati nationals, there is increasing fear that their culture will eventually succumb to Westernization and foreign influence. Such apprehension is justified, for the demographics are not on their side. Emi ratis now flier for only 20 percent of the population (an official estimate, probably inflated) within 20 years, as more foreigners pour in from South Asia, the Far East, Russia, and Africa, the circumstances is likely to fall to the sin-gle digits.But it is hard for locals to grumble too loudly when they have also been seduced by the global consumer ethos. After midday pray-ers on a blazing Friday afternoon, they head for the blissfully cool shopping malls, as do Indian and Filipino families and British expatriates, to scoop up the latest in busy phones and other electronic gadgets. Women display designer handbags over their flowing black abayas but wear blue jeans under them, and many young men co-occurrence their crinkly clean kandouras with a baseball cap instead of the traditional white headdress. Out in the parking lot, families cram the backs of their Range Rovers and Ford Explorers with flexible shopping bags and a months groceries. The good life has created a sedentary life, and with it a sharp rise in obesity and diabetes.As though suddenly seeing the need to change direction, Dubai has begun making desperate attempts to preserve its past. In April 2007 the Dubai Municipality issued a ruling ordering the preservation of more than 2,000 buildings it considered having historical meaning in the United Arab Emirates. But the breakneck development all over the city makes this a fools errand. Glossy advertisements for unbuilt real estate tracts cover the arrivals hall at the airport, fill billboards beside the highway entrance ramps, and push the news off the front pages of the local news-papers. The inside pages promise more one full page ad shows a Venetian gondolier, against a backdrop of faux Mediterranean chic, paddling along an artificial canal, past caf tables with Western and Asian patrons relaxing beneath palm trees. The most widely advertised development is now the Lagoons, a name that, like the Greens, Springs, Lakes, and Meadows, belies th e arid land it occupies.Indeed, image more than oil (little of which ever existed in Dubai anyway) is now the citys most valuable export. But what reality might that image exploit? The city was never one of the great centres of Muslim learning or Arab culture, like Cairo or Damascus. It has always been a centre for trade, a way station for commerce. Even today it boasts no expansive mosques shopping malls are the grandest edifices, and the best-known universities are imported satellite campuses from the United States, England, and Australia. So with no great cultural legacy to celebrate, Dubai has embraced the culture of celebrity. Last February, tiger Woods was once again victorious in the Dubai Desert Classic, and Roger Federer tried (unsuccessfully) to defend his title in the Dubai Tennis Championships. A year ago George Clooney promoted his motion picture Michael Clayton at the Dubai International Film Festival, and Brad Pitt and Angelina Jolie have been spotted frolicking wit h their children on the beach of the Burj Al Arab, the sail-shaped hotel that is the citys current signature landmark.Dubai is often described as an Arabian Disneyland, and the characterization is not wide of the mark. Tourists, residents, and celebrities (including Michael Jackson and Rafael Nadal) have slid down the foaming cascades at the Wild Wadi water park. Across Sheikh Zayed Road, the enclosure for the indoor ski slope at the Mall of the Emirates angles into the sky like a giant airplane hangar tipped on end, gleaming with a streak of lurid colour at nightfall. To accommodate the 15 million tourists a year that the city is planning to host by 2010, another resort complex of 30 hotels and 100 cinemas was sketched out on the city planners boards, but as a sign that even Dubais aspirations have been tempered, the project has been put on hold. Not, however, the Mall of Arabia, which promises to surpass the West Edmonton Mall as the worlds largest shopping and entertainment comp lex.The most weighty feature of Dubai isnt the George Jetson architecture, or even the Burj Dubai, destined to be the tallest building in the world when completed, but the fact that people who would normally be at each others throats in their home countriesIndians and Pakistanis, Sunni and Shiite Muslims, Serbs and Bosnians, Ethiopians and Eritreansmanage to live and work together in remarkable harmony. This is also part of the legacy of Dubai, that for generations it has served as a crossroads of cultures and a transit point for people as well as goods, and so it evolved into a tolerant neutral space where the trivial feuds of other parts of the world have no place. The downside of this polyglot society is a paucity of the shared concerns that can form a favorable knowingness and hold a society together.I dont want Hezbollah running my country, the Lebanese receptionist at a medical clinic says when I claim her thoughts on the fallout of the Israel-Lebanon war. That issue is a nonstarter for the Asian staff who share her office. She was a beautiful, beautiful woman the Pakistani security guard outdoor(a) my apartment building croons, 2 days after the assassination of Benazir Bhutto, who spent part of her political exile in Dubai. Being so far from the caf tables of Lahore or Karachi, it is probably the first chance hes had to pour out praise for the populist leader. Dubai is just a short airplane hop from the crises in Sudan, Iraq, and Palestine, but in an odd irony, this global city remains blissfully alienated from the pressing global issues that surround it. Car bombings in Baghdad and street battles in Gaza seem to exist in some parallel universe far from Dubais beach clubs and poolside barbecues.If talk radio is a barometer of popular sentiment, Dubai lacks social angst, or even concern about the worlds troubles. On Property Week, callers swap tips on the latest real estate investments. On another show, listeners offer advice on ways to kill time i n traffic and compare the brunch buffets and weekend getaway packages offered by five-star hotel chains. One program is disposed to nuanced analysis of rugby, soccer, and cricket matches for United Kingdom and subcontinent expatriates. When the local English daily celebrated its 35th anniversary, readers praised the paper for its coverage of business, sports, and entertainment, but there was no han-k-ering for more articles on inter-national current events, some fright-ening-ly close to home. Life in Dubai is not all whimsical indulgence, however, for vice has arrived as an inseparable part of the global village. Dubais crime rate, still modest by Western standards, has risen to a level that would have been unknown a generation ago.Street crimes are still rare but drug seizures are not, and black markets in consumer goods have sprung up. (In a caper that Butch Cassidy would have envied, a gang of thieves drove two stolen cars through an entrance of the upscale Wafi City Mall, smash ed a jewellery store display window, and made off with the goods.) Where economic adventurism thrives, so does the worlds oldest profession. Prostitutes from China, the Philippines, Russia, Eastern Europe, and the former Soviet republics hover near hotel entrances, hoping to snag returning guests. To its credit, Dubai can be called a true microcosm, but its hard to reckon that a coherent society can be composed of guest workers who have migrated solely for lucrative jobs and have no longterm stake in the citys future.Beneath the veneer of harmony is the disturbing sense that everyone knows his or her place. Class asserts itself in an unsavoury caste system where national and ethnic individualism determines whether one is offered employment or a lease for an apartment. The citys reputation as a haven of safety and security in a troublesome part of the world is upheld by affirming an old world order left by the colonial power Dubai would like to believe it has moved beyond. neighbo rly equality is a noble ideal promoted by the government but flouted in practice, proving once again that the democratic society is still a modern notion, at war with the more widespread tendency of human beings to create a hierarchy. A landlord may refuse to rent apartments to bachelors, the code word for men from the Asian subcontinent working in Dubai who may be supporting wives and children back home.The term would never apply to an unmarried German electrical engineer or a Canadian English teacher. Eight years, a taxi driver replies when I ask how long he has been plying the roads of Dubai, and I know this manner 12 hours a day, six days a week. On Friday afternoons he probably goes to the closest Western Union office, like hundreds of others, to wire money back to his family in Mumbai or Peshawar. Class asserts itself also in the division between servers and the served. I still feel a little awkward when supermarket clerks address me formally and the deliveryman from Pizza Hu t (Ahmad, according to his name tag) is overly grateful for a modest tip.But I remind myself that since Dubai is not a republic and few of its residents come from democratic countries, there is no way its society could resemble one. If someone had to pinpoint one spot on earth that epitomizes the most unsavoury aspects of globalization, Dubai could be Exhibit A. It is a place where the whims of a consumerist society overwhelm a simple native Bedouin culture, the predilections of the affluent obliterate local mood and ecology, and the divide between rich and poor is unapologetically laid bare.Discussion pointsRead the above account of Dubai and discuss the following questions in groups 1. To what extent can the Dubai level be regarded as the epitome of Globalisation? Explain your answer. 2. In what ways can Dubai be regarded as vulnerable? 3. What negative aspects of the Dubai story can you rank? 4. How might these negative aspects be mitigated?