...AG, Zurich, Switzerland ¨ Abstract: The present paper discusses the basic principles of hydraulic turbines, with special emphasis on the use of computational fluid dynamics (CFD) as a tool which is being increasingly applied to gain insight into the complex three-dimensional (3D) phenomena occurring in these types of fluid machinery. The basic fluid mechanics is briefly treated for the three main types of hydraulic turbine: Pelton, Francis and axial turbines. From the vast number of applications where CFD has proven to be an important help to the design engineer, two examples have been chosen for a detailed discussion. The first example gives a comparison of experimental data and 3D Euler and 3D Navier–Stokes results for the flow in a Francis runner. The second example highlights the state-of-the-art of predicting the performance of an entire Francis turbine by means of numerical simulation. Keywords: hydraulic turbines, flow prediction, stage simulation, hill chart, Navier–Stokes and Euler computations NOTATION C, c E g h at h d H H s k K c K u K w n Q R, r T U, u W, w Z a b e f g absolute velocity (m/s) energy per unit mass (m2/s2) gravity (m/s2) atmospheric pressure head (m) vapour pressure head (m) turbine head (m) suction head (m) turbulent kinetic energy (m2/s2) normalized velocity normalized circumferential velocity normalized relative velocity rotational speed (r/min) flowrate (m3/s) radius/radial direction torque (N m) circumferential velocity (m/s) relative velocity (m/s) axial...
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...Conversion of a Propeller Turbine to Full Kaplan Operation at Michigamme Falls By Gerard J. Russell, P.E., American Hydro Corp., York, Pennsylvania, USA, Craig Peterson, P.E., American Hydro Corp., York, Pennsylvania, USA, and Douglas T. Eberlein, P.E., We Energies, Milwaukee, Wisconsin, USA ABSTRACT FERC license renewal stipulations for We Energies’ Michigamme Falls plant included new flow constraints that were outside the existing fixed-blade propeller turbines’ efficiency range. One of the turbines was converted to fully adjustable Kaplan operation to regain the lost generation. Introduction Renewal of the project’s FERC license in October of 2001 required that the minimum flow could be no less than 50% of the maximum flow during a given calendar day. The existing generating units were typical fixed-blade propeller turbines with a very narrow range of efficient operation, so they could not effectively meet this new requirement. We Energies evaluated several options for addressing the new operating regime including spilling the required low flow when necessary, installation of a minimum flow turbine-generator unit, and conversion of one of the propeller units to full adjustable blade Kaplan operation. The Kaplan conversion was chosen as the most effective option to improve the operating efficiency and flexibility of the plant while achieving the required low flow operating capability. This paper describes the Owner’s planning process that resulted in the decision to convert...
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...The Kaplan turbine is an inward flow reaction turbine, which means that the working fluid changes pressure as it moves through the turbine and gives up its energy. Power is recovered from both the hydrostatic head and from the kinetic energy of the flowing water. The design combines features of radial and axial turbines. The inlet is a scroll-shaped tube that wraps around the turbine's wicket gate. Water is directed tangentially through the wicket gate and spirals on to a propeller shaped runner, causing it to spin. The outlet is a specially shaped draft tube that helps decelerate the water and recover kinetic energy. The turbine does not need to be at the lowest point of water flow as long as the draft tube remains full of water. A higher turbine location, however, increases the suction that is imparted on the turbine blades by the draft tube. The resulting pressure drop may lead to cavitation. Variable geometry of the wicket gate and turbine blades allow efficient operation for a range of flow conditions. Kaplan turbine efficiencies are typically over 90%, but may be lower in very low head applications.[2] Current areas of research include CFD driven efficiency improvements and new designs that raise survival rates of fish passing through. Because the propeller blades are rotated on high-pressure hydraulic oil bearings, a critical element of Kaplan design is to maintain a positive seal to prevent emission of oil into the waterway. Discharge of oil into rivers is not desirable...
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...CONCORD LAW SCHOOL OF KAPLAN UNIVERSITY CRIMINAL LAW ESSAY 1 Hal and Wanda had been married for many years. Each weekday Hal, who worked for a data processing firm, left for work at 8am and returned home after 6pm. Wanda worked from their home as a telemarketer. As their 20th wedding anniversary approached, Hal decided to prepare a romantic surprise for Wanda. On the day of their anniversary Hal left work at 1pm and drove to the local florist where he purchased a dozen long stem roses. He then drove home intending to surprise Wanda with the flowers and spend the entire afternoon alone with her. When Hal arrived at his home he looked in the window of the office Wanda used to do her telemarketing calls and observed Wanda in what he believed to be a passionate embrace with his neighbor, Norm. Hal, an overly jealous man, had long suspected that Norm harbored desires for his wife. Believing that Wanda and Norm had just engaged in sexual relations, he flew into a rage, ran to the garage and retrieved a revolver he kept in a locked box. He then opened a safe located in the garage in which he stored bullets, removed 6 bullets and loaded the revolver. He then ran back to the front of the house just as Norm was leaving. Hal shot Norm, killing him instantly. In actuality Norm had dropped by Hal's and Wanda's home to drop off an anniversary gift for the two of them and Wanda was giving Norm a hug to thank him when Hal had looked through the window. Hearing the shot Wanda ran from the house...
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...In my last two years of competing against Runners and Triathletes there have been a few injuries, chronic fatigue and potential burnout. I decided to step back this year while training for the marathon by preventing myself in falling in the same pattern again. Often times, the best barometer of feedback is not in watts, heart data or fancy graphs. Some of the best feedback comes from our gut instincts. Finding the joy in training and being opening up to being more flexible in our regimen is just as important as all the hard interval work or getting in the volume. This said, I decided to listen to my inner voice which said, “I think I need to rest more today.” That inner voice often sent me an SOS signal calling for either a brief physical or mental break. The best advice that I can give to you as a runner is to speak to yourself as if you were your own best friend. What would you say to a good friend if she or he felt pressure to so something on plan, but knew deep inside what they really needed? What would you say to your friend if he or she said that she was really, really tired and not up for doing something you had planned together? You’d probably say that “it’s okay – we’ll get it in another time.” The best runners, who perform well consistently, often follow a structured training plan. However, they also have learned the art of listening to that inner voice and allowed for flexibility within their plan. As a runner, you need to understand and trust that it’s...
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...Old Dog, New Trick When my daughter, Marisa turned eleven, a friend at school told her about an event the YMCA was sponsoring over the summer called, “Kids can do 26.2”. It was to promote kids staying active during the summer. I helped her train and get ready for the race for ten weeks. The day before the race, we went to the Amory to pick up her bib and t shirt. The armory was a flurry of activity with sports, snack and other race vendors. I saw a slim, very fit woman setting up a booth. I picked up one of the pamphlets she laid out on the table. “Moms in Motion” it said. “Hi,” she said extending her hand toward me. “I’m Deb. Are you a runner?” I smiled and shook my head. “No, I’m too old to start that”. She laughed. “You’re never too old to start something new!” I listened intently as she spoke about the “Moms” and I have to admit that secretly, I wanted to try it. Deb asked me where I lived and then proceeded to tell me that there was a new leader who wanted to start a team in Webster. She wrote down all the information and handed me back the pamphlet. The next morning, my husband, son, daughter and I left for Frontier Field. “Are you nervous?” I asked her. “No way”, she replied. I’m excited!” “You’ll do great!” My husband told her. Frontier Field was mobbed. Kids and parents were everywhere. The race atmosphere was exhilarating. There was music, spectators, and other vendors. There was an announcement that the race was about to start. We...
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...The Maze Runner book review The Maze Runner is very similar to the Hunger games books as it almost has the same story line. I would suggest to anyone who enjoyed reading the Hunger Games, they would very much relish the chance to read The Maze Runner. The basic plot of the book is the lead character Thomas wakes up in an abandoned elevator by himself and has no memories of life before the elevator he wakes up in, the only memories he had were not specific and were bare such as his school, however he doesn’t remember any people faces and only remembers his name. The elevator doors open and he finds himself in a huge field with boys aged 12-18. The boys are known as Gladers and use their own dialect every other words so the first couple of chapters are very hard to understand but once you get the hand of it, it’s all very easy. All the boys lived in huts inside this field and there are massive walls surrounding them so Thomas is very unsure of his position. Outside the walls there is a huge maze which runs on for miles and miles, which seems to run nowhere. Everyday this group of boys called the runners try to find a way out of the maze. However they have to return every night as the wall go up and the boys would be stuck outside the maze where these horrible creatures called Griever’s come out and hunt down the children. These creatures are half animal half machine and have saws for arms. Thomas came up with a dangerous plan to escape. The plan works, but half of the group dies...
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...Case Study: Marathon Runners at Different levels By: Alain Kayembe Questions 1. Based on the principles of SLII model, how would you describe the runners in group 1? What kind of leadership do they want from David, and what kind of leadership does David seem prepared to give them? The runners in Group 1 some runners are novices and don’t have any marathon’s experience at all. According to the SLII model, the group 1 could be categorized as having a low to some competence with a low commitment (D2). It seems like they are expecting from David a type of leadership that requires a high directive and high supportive in his coaching approach. Unfortunately, David doesn’t seem to be prepared to give them that type of leadership as he finds their questions and concerns somewhat annoying. 2. How would describe the fit between the runners in group 2 and David’s coaching style Discuss. Clearly, it’s a total mismatch between what the runners expect from David as a coach, versus what he’s willing and able to do for them. First, the group is looking for David’s coaching approach to be more direct and supportive with all hands on all aspects of their training. In contrast, David seems to be coaching passively, almost like delegating everything to the runners. 3. The experienced runners in group 3 appear to be a challenge to David. Using SLII, explain why David appears ineffective with this group. The approach David is taking with this group is ineffective by itself...
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...Liberman, an avid marathon runner and trainer decided to open his own business a one-stop shop selling running gears and equipments, after being retrenched from his office day job. He decided to venture into this business in particular because of his passion for running and being healthy and fit. There are no shops selling running gears and equipments in his town yet. Any avid or non avid runners who wishes to buy any running gears and equipments has to place their orders on online shops to pre-order their gears and it takes about 2 to 4 months tops for their order to arrive. They not only have to pay the price of the item they have just purchased but also the postage costs are borne by the customers. Being an avid runner himself, Liberman then opened up a shop selling running gears and equipments of various brands, known as Running-Man Shop. The selling prices of these running gears and equipments are set to be the same as the online shops which his customers usually visit. Liberman gloats that opening Running-Man Shop is better than having his customers making online purchases as they do not have to pay for postage costs and Running-Man Shop can cater to the market niche that has been ignored. His shop has become very popular among runners, and his one-stop shop selling running gears and equipments has been very busy since in first opens. Running-Man Shop has become the first one-stop shop famous for its good quality and various branded running gears and equipments. Running-Man...
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...muscles because of the thin air. After the training period, a return to sea level can lead a body to acclimatize to the lower level of oxygen, which results in improving the delivery of more oxygen to the muscles and an increase of their VO2 max. Athletes from many different sports use this kind of training to aid them. However, there is debate in which altitude might just have a physiological benefit. Critics question whether it is just a psychological advantage that helps athlete’s performance once they return back to sea level. Nummela and Rusko’s aim of this study was to “establish the effects of living high and training low on sea-level performance in sprint athletes”(2000, p411). The chosen subjects were made up of eighteen 400m runners or hurdlers, all of which were well-trained and performing at high intensities (Nummela & Rusko, 2000,p412). The participating subjects were split into two groups for the study: six men and two women, who ran for the Finnish national team. They were required to live at altitude and to train at sea level, while the remaining ten men both lived and trained at sea level (Nummela & Rusko, 2000,p412). The average age of the group living at the altitude house was 21.8 years of age, while the average age of the sea level group was 21.9 years of age (Nummela & Rusko, 2000,p412).). The study was conducted over two lengthy years. Two annual outdoor seasons were used, both consecutively in...
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...As;dlkfjlsdjflkjsdlfkj;lsdjfjfjslfjlksdfj * Study Resources * By School * By Subject * By Standardized Tests * By Book * Upload Documents * Tutors * Get Homework Help * About Tutors * Become a Tutor * Flashcards * Find Flashcards * Create Flashcards * About Flashcards * Log-in * Sign Up ------------------------------------------------- 50. there is pressure on the mayor to reduce the fare Home Kaplan University MICROECONO MICROECONO BU224 BUS224_02_OSBORNE_TIFFANY_ unit9 Download Document 1 - 2 of 6 This preview has blurred sections. Sign up to View Full Document Skyscraper City has a subway system, for which a one-way fare is $1.50. There is pressure onthe mayor to reduce the fare by one-third, to $1.00. The mayor is dismayed, thinking that thiswill mean Skyscraper City is losing one-third of its revenue from sales of subway tickets. Themayor’s economic adviser reminds her that she is focusing only on the price effect and ignoringthe quantity effect. Explain why the mayor’s estimate of a one-third loss of revenue is likely tobe an overestimate.Page 1 of 6 Because when a lower price is given more tickets will be sold therefor there will be additionalrevenue coming in.2.Bob, Bill, Ben, and Brad Baxter have just made a documentary movie about their basketballteam. They are thinking about making the movie available for download on the Internet, and theycan act as a...
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...gone by since Kaplan University Online restructured its business model. I was part of the massive laid off that shook the online for-profit schools back in the fall of 2011. Who is Kaplan University Online? Kaplan University Online is a division of the Washington Post (Hechinger, 2013, ∂ 1) an online university of higher learning education offering certificates, associates, bachelors and graduate degrees (Kaplan University, n.d., ∂ 1). Kaplan’s mission and market niche was to enroll adults or working adults who want to complete a college degree but neither has the time to enroll in a traditional campus. That being said, Kaplan was new player in the market competing against other for profit schools such as Devry Institute, ITT, Phoenix University to name a few. In 2007, I was recruited by Kaplan’s HR department to work as an inside sales representative. Myself and 12 other individuals went through a 2-week training class covering Kaplan’s culture, Fafsa (free application for student aid), compliance and boilerplate sales script. The training was intense and strict focusing mostly on the sales script and preaching Kaplan’s ethics, integrity and mission. Like any other jobs I had before this; I took the challenge seriously and was focus on becoming the best at my trade. After my first week on the sales floor, I found myself enrolling more students than any other Kaplan University sales rep. My recognition and reputation quickly escalated to the CEO of Kaplan Inc and other...
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...vegetative state. Meanwhile, Thomas learns more about the Glade, and he feels at home like he's been there before. He learns that the Gladers have been trying to solve the Maze for two years and that the Grievers sting can cause you to recall almost complete memories from the past. The process is painful and dreaded by other Gladers. He feels oddly connected to the new girl and also befriends a young Glader named Chuck, as well as a boy named Newt. On the other hand, he has a somewhat negative relationship with Gally, who is suspicious of Thomas and claims that he has seen him, after he was stung by a Griever, in a process known as the Changing. Thomas also feels an inexplicable urge to be a Runner, the people who explore, map out, and try to find a way out of the Maze. One day, one Runner and the "leader of the Glade," Minho and Alby return late from the job. Alby has been stung by a Griever. As the doors are about to close...
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... * Performance refers to output results and their outcomes obtained from processes, products, and services that permit evaluation and comparison relative to goals, standards, past results, and other organisations. Performance can be expressed in non-financial and financial terms. * Measurement refers to numerical information that quantifies input, output, and performance dimensions of processes, products, services, and the overall organisation (outcomes). Performance measures might be simple (derived from one measurement) or composite. Using a Balanced Scorecard Approach to Measure Performance Robert S. Kaplan and David P. Norton have developed a set of measures that they refer to as "a balanced scorecard." These measures give top managers a fast but comprehensive view of the organization's performance and include both process and results measures. Kaplan and Norton compare the balanced scorecard to the dials and indicators in an airplane cockpit. For the complex task of flying an airplane, pilots need detailed information about fuel, air speed, altitude, bearing, and other indicators that summarize the current and predicted environment. Reliance on one instrument can...
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...mix and volume variance, mix variance, volume variance, other revenue analysis, market share variance, industry volume variance, expense variance in the analysis statement given then it would be useful data for analyzing the firm's January performance because these data can inform us the difference between the revenue and expenses. Balanced Scorecard Basics The balanced scorecard is a strategic planning and management system that is used extensively in business and industry, government, and nonprofit organizations worldwide to align business activities to the vision and strategy of the organization, improve internal and external communications, and monitor organization performance against strategic goals. It was originated by Drs. Robert Kaplan (Harvard Business School) and David Norton as a performance measurement framework that added strategic non-financial performance measures to traditional financial metrics to give managers and executives a more 'balanced' view of organizational performance. While the phrase...
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