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43-623: The Kaplan turbine was an evolution of the Francis turbine . Its invention allowed efficient power production in low- head applications which was not possible with Francis turbines. The head ranges from 10 to 70 metres (33 to 230 ft) and the output ranges from 5 to 200 MW. Runner diameters are between 2 and 11 metres (6 ft 7 in and 36 ft 1 in). Turbines rotate at a constant rate, which varies from facility to facility. That rate ranges from as low as 54.5 rpm ( Albeni Falls Dam ) to 450 rpm. Kaplan turbines are now widely used throughout

86-436: 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 because of the waste of resources and resulting ecological damage. Kaplan turbines are widely used throughout the world for electrical power production. They cover the lowest head hydro sites and are especially suited for high flow conditions. Inexpensive micro turbines on

129-476: A demonstration unit at Poděbrady (now in Czechia). In 1922, Voith introduced an 1100 HP (about 800 kW) Kaplan turbine for use mainly on rivers. In 1924 an 8 MW unit went on line at Lilla Edet , Sweden. This launched the commercial success and widespread acceptance of Kaplan turbines. The Kaplan turbine is an inward flow reaction turbine, which means that the working fluid changes pressure as it moves through

172-414: A new application in offshore wave energy generation, see Wave Dragon . The Kaplan turbine is the most widely used of the propeller-type turbines, but several other variations exist: https://www.wws-wasserkraft.at/en Francis turbine The Francis turbine is a type of water turbine . It is an inward-flow reaction turbine that combines radial and axial flow concepts. Francis turbines are

215-572: A reservoir is filled by the turbine (acting as a pump) driven by the generator acting as a large electrical motor during periods of low power demand, and then reversed and used to generate power during peak demand. These pump storage reservoirs act as large energy storage sources to store "excess" electrical energy in the form of water in elevated reservoirs. This is one of a few methods that allow temporary excess electrical capacity to be stored for later utilization. James B. Francis James Bicheno Francis (May 18, 1815 – September 18, 1892)

258-436: A wide range of heads and flows. This versatility, along with their high efficiency, has made them the most widely used turbine in the world. Francis type units cover a head range from 40 to 600 m (130 to 2,000 ft), and their connected generator output power varies from just a few kilowatts up to 1000 MW. Large Francis turbines are individually designed for each site to operate with the given water flow and water head at

301-509: Is Q = 3.33 h 1 3 / 2 ( L − 0.2 h 1 ) {\textstyle Q=3.33h_{1}^{3/2}(L-0.2h_{1})} where: Q is the discharge in cubic feet per second over the weir, L is the length of the weir in feet, and h 1 is the height of the water above the top of the weir. He remained at the Locks and Canal Company for his entire career, until retirement in 1884 at

344-408: 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

387-404: Is a type of reaction turbine, a category of turbine in which the working fluid comes to the turbine under immense pressure and the energy is extracted by the turbine blades from the working fluid. A part of the energy is given up by the fluid because of pressure changes occurring on the blades of the turbine, quantified by the expression of degree of reaction , while the remaining part of the energy

430-472: Is equal to that at the inlet to the draft tube. Using the Euler turbine equation, E / m = e = V w1 U 1 , where e is the energy transfer to the rotor per unit mass of the fluid. From the inlet velocity triangle, and Therefore The loss of kinetic energy per unit mass at the outlet is V f2 /2 . Therefore, neglecting friction, the blade efficiency becomes i.e. Degree of reaction can be defined as

473-445: Is extracted by the volute casing of the turbine. At the exit, water acts on the spinning cup-shaped runner features, leaving at low velocity and low swirl with very little kinetic or potential energy left. The turbine's exit tube is shaped to help decelerate the water flow and recover the pressure. Usually the flow velocity (velocity perpendicular to the tangential direction) remains constant throughout, i.e. V f1 = V f2 and

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516-455: Is necessary, as these are major parameters affecting power production. Draft tube : The draft tube is a conduit that connects the runner exit to the tail race where the water is discharged from the turbine. Its primary function is to reduce the velocity of discharged water to minimize the loss of kinetic energy at the outlet. This permits the turbine to be set above the tail water without appreciable drop of available head. The Francis turbine

559-838: The Croton River in New York. He also consulted on the dam at Saint Anthony Falls on the Mississippi River . Their son James fought in the American Civil War as a second lieutenant in 1861. He was wounded in the hand at the Battle of Antietam as a captain , and finished the war in July 1865 as lieutenant colonel . Francis was elected as a member of the American Philosophical Society in 1865. In 1845, Francis developed

602-470: The Forest Hills , Hyde Park , Franklin park and Roslindale sections of the city that were subject to flooding. Francis stayed active on all levels of involvement in the city of Lowell, and served as an alderman from 1862 to 1864. In 1865, Francis researched and published his findings on cast iron, and its use in structural columns in "The Strength of Cast-Iron Columns". In 1874, Francis served on

645-694: The South Fork Dam in Johnstown, Pennsylvania, broke, killing over 2,200 people.   Although the report was completed by January 1890, it was immediately suppressed and not released to other ASCE members or the public until mid-1891, two years after the 1889 flood.   Francis himself presented the results of the investigation at the ASCE convention in Chattanooga, Tennessee.  The other three committee members did not attend.  Although Francis’ name headed

688-412: The electric generators generally ranges from just a few kilowatts up to 1000 MW, though mini-hydro installations may be lower. The best performance is seen when the head height is between 100–300 metres (330–980 ft). Penstock diameters are between 1 and 10 m (3.3 and 32.8 ft). The speeds of different turbine units range from 70 to 1000  rpm . A wicket gate around the outside of

731-592: The turbine's rotating runner controls the rate of water flow through the turbine for different power production rates. Francis turbines are usually mounted with a vertical shaft, to isolate water from the generator. This also facilitates installation and maintenance. Water wheels of different types have been used for more than 1,000 years to power mills of all types, but they were relatively inefficient. Nineteenth-century efficiency improvements of water turbines allowed them to replace nearly all water wheel applications and compete with steam engines wherever water power

774-607: The American Society of Civil Engineers committee to investigate the cause of the breach of the Mill River dam in Massachusetts .   Also on the committee were engineers Theodore Ellis and William Worthen. The investigation proceeded quickly and its report was published within a month of the disaster. It concluded that no engineer was responsible for the design and that it was the “work of non-professional persons”. “The remains of

817-511: The Kaplan turbine model are manufactured for individual power production designed for 3 m of head which can work with as little as 0.3 m of head at a highly reduced performance provided sufficient water flow. Large Kaplan turbines are individually designed for each site to operate at the highest possible efficiency, typically over 90%. They are very expensive to design, manufacture and install, but operate for decades. They have recently found

860-551: The age of 69, and remained on as a consultant right up until his death. His son James took over as chief engineer. The rest of his life he spent with his wife Sarah, and their six children in their home on Worthen Street, which was Whistler's old home and now is the Whistler House Museum of Art . Francis was called to duty in 1889 as a member of an ASCE committee to examine the cause of the Johnstown Flood disaster when

903-502: The age of 77, and is buried at Lowell Cemetery under a massive pillar of cut granite stones, symbolizing the stones used to make the canals. For all his contributions to the world of engineering and his personal generosity, the following are named in his honor: Today, the Francis turbine is the most widely used water turbine in the world, including China's new Three Gorges Dam as the world's second largest hydroelectric power station in

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946-500: The city from great disaster Francis was awarded a massive silver pitcher and a salver by the City of Lowell. In 1886, Francis teamed up with two other civil engineers; Eliot C. Clarke and Clemens Herschel to study and publish their findings in the "Prevention of Floods in the Valley of Stony Brook" which laid out a flood prevention system for the city of Boston . The detailed study reviewed

989-522: The dam indicate defects of workmanship of the grossest character.” Francis originated scientific methods of testing hydraulic machinery, and was a founding member of the American Society of Civil Engineers and its president in 1880. In 1883, Francis completed his calculation standards for water flow rates, now known as the Francis equation or Francis formula , usually used in fluid dynamics in conjunction with calculating weirs . The equation

1032-406: The design of high-efficiency turbines to precisely match a site's water flow and pressure ( water head ). A Francis turbine consists of the following main parts: Spiral casing : The spiral casing around the runner of the turbine is known as the volute casing or scroll case. Throughout its length, it has numerous openings at regular intervals to allow the working fluid to impinge on the blades of

1075-545: The first sprinkler systems ever devised in the United States. However, any use of the system would flood the entire structure and its contents. It was not until 1875 that Henry S. Parmelee invented a sprinkler head that activated only one head at a time. Francis became fascinated with and tinkered with turbine designs, after Uriah A. Boyden first demonstrated his Boyden turbine in Lowell. The two engineers worked on improving

1118-477: The gates saved the city of Lowell from the devastating floods of 1852, and again in 1936 , 1938 , 2006 , and 2007 by preventing the Merrimack River from entering the canal system. However, arson damage to the wooden gate in the 1970s, and the difficult method of dropping it (by breaking a large chain link) prompted the city to use a more modern steel-beam bulkhead in its place in 2006. For his efforts in saving

1161-436: The guide and stay vanes is to convert the pressure energy of the fluid into kinetic energy. It also serves to direct the flow at design angles to the runner blades. Runner blades : Runner blades are the heart of any turbine. These are the centers where the fluid strikes and the tangential force of the impact produces torque causing the shaft of the turbine to rotate. Close attention to design of blade angles at inlet and outlet

1204-456: The highest possible efficiency, typically over 90% (to 99% ). In contrast to the Pelton turbine , the Francis turbine operates at its best completely filled with water at all times. The turbine and the outlet channel may be placed lower than the lake or sea level outside, reducing the tendency for cavitation . In addition to electrical production , they may also be used for pumped storage , where

1247-458: The late 1840s and early 1850s, completed the 5.6 mile long Lowell canal system, and greatly increased the industrial power of the thriving industrial city's mill complexes. During his work on the Lowell systems, Francis was also consulted on many other water projects nationwide. When New York needed to increase their water supply, he consulted on the construction of the Quaker Bridge Dam on

1290-425: The most common water turbine in use today, and can achieve over 95% efficiency. The process of arriving at the modern Francis runner design took from 1848 to approximately 1920. It became known as the Francis turbine around 1920, being named after British-American engineer James B. Francis who in 1848 created a new turbine design. Francis turbines are primarily used for producing electricity. The power output of

1333-433: The ratio of pressure energy change in the blades to total energy change of the fluid. This means that it is a ratio indicating the fraction of total change in fluid pressure energy occurring in the blades of the turbine. The rest of the changes occur in the stator blades of the turbines and the volute casing as it has a varying cross-sectional area. For example, if the degree of reaction is given as 50%, that means that half of

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1376-551: The report, the de facto chairman of the committee was Max Becker, a railroad engineer based in Pittsburgh with virtually no experience in dams or hydraulic engineering.  According to Francis, it was Becker who delayed the release of the report.  A detailed discussion of the South Fork investigation, the participating engineers, and the science behind the 1889 flood was published in 2018. Francis died on September 18, 1892, at

1419-400: The runner. These openings convert the pressure energy of the fluid into kinetic energy just before the fluid impinges on the blades. This maintains a constant velocity despite the fact that numerous openings have been provided for the fluid to enter the blades, as the cross-sectional area of this casing decreases uniformly along the circumference. Guide and stay vanes : The primary function of

1462-555: The same principles. S. B. Howd obtained a US patent in 1838 for a similar design. In 1848 James B. Francis , while working as head engineer of the Locks and Canals company in the water wheel-powered textile factory city of Lowell, Massachusetts , improved on these designs to create more efficient turbines. He applied scientific principles and testing methods to produce a very efficient turbine design. More importantly, his mathematical and graphical calculation methods improved turbine design and engineering. His analytical methods allowed

1505-876: The total energy change of the fluid is taking place in the rotor blades and the other half is occurring in the stator blades. If the degree of reaction is zero it means that the energy changes due to the rotor blades is zero, leading to a different turbine design called the Pelton Turbine . The second equality above holds, since discharge is radial in a Francis turbine. Now, putting in the value of 'e' from above and using V 1 2 − V f 2 2 = V f 1 2 cot ⁡ α 2 {\displaystyle V_{1}^{2}-V_{f2}^{2}=V_{f1}^{2}\cot \alpha _{2}} (as V f 2 = V f 1 {\displaystyle V_{f2}=V_{f1}} ) Francis turbines may be designed for

1548-409: 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

1591-748: The turbine. And in 1848, Francis and Boyden successfully improved the turbine with what is now known as the Francis turbine . Francis's turbine eclipsed the Boyden turbine in power by 90%. In 1855, Francis published these findings in the "Lowell Hydraulic Experiments". In 1850, Francis ordered the construction of the Great Gate over the Pawtucket Canal to protect the downtown mills from any devastating floods. This project quickly became known as "Francis's Folly", given that no one believed it would work, let alone ever be needed. But less than two years later, in 1852,

1634-447: 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. Current areas of research include computational fluid dynamics (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,

1677-506: The world in high-flow, low-head power production. Viktor Kaplan, living in Brno , Austria-Hungary (now in Czechia ), obtained his first patent for an adjustable blade propeller turbine in 1912. But the development of a commercially successful machine would take another decade. Kaplan struggled with cavitation problems, and in 1922 abandoned his research for health reasons. In 1919 Kaplan installed

1720-641: Was a British-American civil engineer, who invented the Francis turbine . James Francis was born in South Leigh , near Witney , Oxfordshire, in England, United Kingdom. He started his engineering career at the early age of seven as he worked as his father's apprentice at the Porth Cawl Railway and Harbor Works in South Wales . When he turned 18, he decided to emigrate to the United States, in 1833. His first job

1763-516: Was available. After electric generators were developed in the late 1800s, turbines were a natural source of generator power where potential hydropower sources existed. In 1826 the French engineer Benoit Fourneyron developed a high-efficiency (80%) outward-flow water turbine. Water was directed tangentially through the turbine runner, causing it to spin. Another French engineer, Jean-Victor Poncelet , designed an inward-flow turbine in about 1820 that used

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1806-522: Was born March 30, 1840, and then they had five more children. In 1841 came his first major project for the company. Francis was to analyse how much water each mill factory was using from the company's channel system. Impressed by his abilities, the company named him "Manager of Locks and Canals" in 1845. As manager and chief engineer, Francis was responsible for the construction of the Northern Canal and Moody Street Feeder . These two canals, built in

1849-760: Was in Stonington, Connecticut , as an assistant to the railway engineer George Washington Whistler Jr. , working on the New York and New Haven Railroad . A year later, James and his boss, Whistler, travelled north to Lowell, Massachusetts , where at the age of 19, he got a draftsman job with the Locks and Canal Company , and Whistler became chief engineer. A few years later, in 1837, Whistler resigned, and went to work on Russia's major railroads. Before departing, he appointed Francis chief engineer, and sold him his house on Worthen Street. In same year, James married Sarah W. Brownell in Lowell on July 12. Their first son, James Jr.,

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