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Water turbines were developed in the nineteenth century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy source.
The migration from water wheels to modern turbines took about one hundred years. Development occurred during the Industrial revolution, using scientific principals and methods. They also made extensive use of new materials and manufacturing methods developed at the time.
The word turbine was coined by the French engineer Claude Bourdin in the early 19th century and is derived from the Latin word for "whirling" or a "vortex". The main difference between early water turbines and water wheels is a swirl component of the water which passes energy to a spinning rotor. This additional component of motion allowed the turbine to be smaller than a water wheel of the same power. They could process more water by spinning faster and could harness much greater heads. (Later, impulse turbines were developed which didn't use swirl).
In 1820, Jean V. Poncelet developed an inward-flow turbine.
In 1826 Bénoit Fourneyron developed an outward-flow turbine. This was an efficient machine (~80%) that sent water through a runner with blades curved in one dimension. The stationary outlet also had curved guides.
In 1844 Uriah A. Boyden developed an outward flow turbine that improved on the performance of the Fourneyron turbine. Its runner shape was similar to that of a Francis turbine.
In 1849, James B. Francis improved the inward flow reaction turbine to over 90% efficiency. He also conducted sophisticated tests and developed engineering methods for water turbine design. The Francis turbine, named for him, is the first modern water turbine. It is still the most widely used water turbine in the world today.
Inward flow water turbines have a better mechanical arrangement and all modern reaction water turbines are of this design. Also, as the swirling mass of water spins into a tighter rotation, it tries to speed up to conserve energy. This property acts on the runner, in addition to the water's falling weight and swirling motion. Water pressure decreases to zero as it passes through the turbine blades and gives up its energy.
Around 1913, Victor Kaplan created the Kaplan turbine, a propeller type machine. It was an evolution of the Francis turbine but revolutionized the ability to develop low head hydro sites.
All common water machines until the late 19th century (including water wheels) were reaction machines; water's pressure head acted on the machine and produced work. A reaction turbine needs to fully contain the water during energy transfer.
In 1879Events January January 11 Anglo-Zulu War begins January 22 Zulu troops massacre British troops at the Battle of Isandlwana. At Rorke's Drift, outnumbered British soldiers drive the attackers away after hours of fighting. February February 12 At New York C by Lester PeltonLester Allan Pelton ( 1829 March 14, 1908), was an American inventor who created the impulse water turbine. He was born in Vermillion, Ohio in 1850 and immigrated to California during the the gold rush. Pelton made his living as a carpenter and a millwrig invented a machine that worked off a completely different concept. The Pelton wheelWalchensee, Germany hydro power station A pelton wheel is one of the most efficient types of water wheel. Function Nozzles direct forceful streams of water against a series of spoon shaped buckets mounted around the edge of a wheel. Each bucket reverses t, named for him, works with impulse; water pressure is turned into kinetic energy with a nozzleA nozzle is a mechanical device designed to control the characteristics of a fluid flow as it exits from an enclosed chamber into some medium. Frequently the goal is to increase the kinetic energy of the flowing medium at the expense of its pressure energ. The resulting water jet impacts curved turbine blades, reversing the water's flow, causing the runner to spin. Turgo turbineThe Turgo turbine is an impulse water turbine designed for medium head applications. Developed in 1919 by as a modification of the pelton wheel, the turgo has some advantages over francis and pelton designs for certain applications. First, the runner is l and Crossflow turbinesThe Banki turbine (also known as the Michell Crossflow or Ossberger turbine) is a hydropower system similar in appearance to an over-shot water wheel. Unlike the water wheel, however, it uses a nozzle and blades instead of buckets. The "middle" of the Ban were later impulse designs.
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