 Francis turbine (courtsey Voith-Siemens). The Francis turbine was developed by James B. Francis. It is an inward flow reaction turbine that combines radial and axial flow concepts. Image File history File links M_vs_francis_schnitt_1_zoom. ...
Image File history File links M_vs_francis_schnitt_1_zoom. ...
Kaplan turbine and electrical generator cut-away view. ...
James Bicheno Francis (May 18, 1815 – September 18, 1892) was a British-American engineer. ...
A reaction is the following: In physics, a reaction (physics) is defined by Newtons third law: For every action there is an equal and opposite reaction. The idea that any given force has a pair or opposite force. ...
WWII era steam turbine used for ship propulsion. ...
Francis turbines are the most common water turbine in use today. They operate in a head range of ten meters to several hundred meters and are primarily used for electrical power production. Kaplan turbine and electrical generator cut-away view. ...
In fluid dynamics, head refers to the constant right hand side in the incompressible steady version of Bernoullis equation. ...
Development
 Francis Runner, Grand Coulee Dam Water wheels have been used historically to power mills of all types, but they are inefficient. 19th century efficiency improvements of water turbines allowed them to compete with steam engines (wherever water was available). Image File history File links Download high resolution version (665x761, 28 KB)Francis turbine parts This file came from: http://www. ...
Image File history File links Download high resolution version (665x761, 28 KB)Francis turbine parts This file came from: http://www. ...
Download high resolution version (790x1024, 54 KB)Francis Runner, Grand Coulee Dam this image is from: http://users. ...
Download high resolution version (790x1024, 54 KB)Francis Runner, Grand Coulee Dam this image is from: http://users. ...
An overshot water wheel standing 42 feet high powers the Old Mill at Berry College in Rome, Georgia A water wheel (also waterwheel, Norse mill, Persian wheel or noria) is a hydropower system; a system for extracting power from a flow of water. ...
Kaplan turbine and electrical generator cut-away view. ...
A steam engine is a heat engine that makes use of the thermal energy that exists in steam, converting it to mechanical work. ...
In 1826 Benoit Fourneyron developed a high efficiency (80%) outward flow water turbine. Water was directed tangentially through the turbine runner causing it to spin. Jean V. Poncelet designed an inward-flow turbine in about 1820 that used the same principles. S. B. Howd obtained a U.S. patent in 1838 for a similar design. 1826 was a common year starting on Sunday (see link for calendar). ...
Bénoit Fourneyron was born in Saint-Étienne, France in 1802. ...
Jean-Victor Poncelet (July 1, 1788 - December 22, 1867) was a mathematician and engineer who did much to revive projective geometry. ...
1820 was a leap year starting on Saturday (see link for calendar). ...
1838 was a common year starting on Monday (see link for calendar). ...
In 1848 James B. Francis improved on these designs to create a turbine with 90% efficiency. He applied scientific principles and testing methods to produce the most efficient turbine design ever. More importantly, his math and graphical calculation methods improved the state of the art of turbine design and engineering. His analytical methods allowed confident design of high efficiency turbines to exactly match a site's flow conditions. 1848 is a leap year starting on Saturday of the Gregorian calendar. ...
James Bicheno Francis (May 18, 1815 – September 18, 1892) was a British-American engineer. ...
Theory of operation The Francis turbine is a reaction turbine, which means that the working fluid changes pressure as it moves through the turbine, giving up its energy. A casement is needed to contain the water flow. The turbine is located between the high pressure water source and the low pressure water exit, usually at the base of a dam. A reaction is the following: In physics, a reaction (physics) is defined by Newtons third law: For every action there is an equal and opposite reaction. The idea that any given force has a pair or opposite force. ...
Scrivener Dam, in Canberra, Australia, was engineered to withstand a once-in-5000-years flood event A dam is a barrier across flowing water that obstructs, directs or retards the flow, often creating a reservoir, lake or impoundment. ...
The inlet is spiral shaped. Guide vanes direct the water tangentially to the runner. This radial flow acts on the runner vanes, causing the runner to spin. The guide vanes (or wicket gate) may be adjustable to allow efficient turbine operation for a range of water flow conditions.
As the water moves through the runner its spinning radius decreases, further acting on the runner. Imagine swinging a ball on a string around in a circle. If the string is pulled short, the ball spins faster. This property, in addition to the water's pressure, helps inward flow turbines harness water energy.
Francis Turbine and generator Francis Turbine Image is from: http://de. ...
| Guide vanes at minimum flow setting (cut-away view) Francis Turbine LowFlow Image from: http://de. ...
| Guide vanes at full flow setting (cut-away view) Francis Turbine HighFlow Image is from: http://de. ...
| At the exit, water acts on cup shaped runner features, leaving with no swirl and very little kinetic or potential energy. The turbine's exit tube is specially shaped to help decelerate the water flow and recover kinetic energy. Kinetic energy is energy that a body has as a result of its speed. ...
Potential energy is stored energy. ...
Application
 Francis Inlet Scroll, Grand Coulee Dam Large francis turbines are individually designed for each site to operate at the highest possible efficiency, typically over 90%. They are best suited for sites with high flows and low to medium head. Francis Turbines are very expensive to design, manufacture and install, but operate for decades. Download high resolution version (1024x790, 138 KB)Francis turbine inlet scroll, Grand Coulee Dam this image is from: http://users. ...
Download high resolution version (1024x790, 138 KB)Francis turbine inlet scroll, Grand Coulee Dam this image is from: http://users. ...
In addition to electrical production, they may also be used for pumped storage; where a reservoir is filled by the turbine (acting as a pump) during low power demand, and then reversed and used to generate power during peak demand. Diagram of the TVA pumped storage facility at Racoon Mountain Pumped storage hydroelectricity is a method of storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations. ...
Francis turbines may be designed for a wide range of heads and flows. This, along with their high efficiency, has made them the most widely used turbine in the world.
Inexpensive francis microturbines are manufactured for individual power production with as little as ten feet of head.
See also Hydroelectricity is a form of hydropower used to produce electricity. ...
Hydraulic turbine and electrical generator. ...
WWII era steam turbine used for ship propulsion. ...
Kaplan turbine and electrical generator cut-away view. ...
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