Jonval turbine and its Applications

The Jonval turbine is a water turbine design invented in France in 1837 and brought into widespread use in the United States around 1850.The Jonval turbine is a "mixed flow" turbine design.The mixed flow design is ideal for low head applications common in the Eastern United States.Smaller size, higher speed, higher power, lower cost, and the ability to operate efficiently with variable water levels led to these and other types of water turbines displacing vertical water turbines as the primary source of power for U.S.industry.A Jonval turbine is a horizontal water turbine.The water descends through fixed curved guide vanes that direct the flow sideways onto curved blades on the runner.It is named after Feu Jonval who invented it.Jonval combined ideas from European mathematicians and engineers, including the use of curved blades.This new turbine failed to satisfy the public interest in seeing the waterwheels in action, which might have been considered a minor drawback at the time.This type is more efficient when fully gated, but some Francis turbine designs are more efficient when partially gated.The usual orientation of waterwheels was horizontal, and the first devices were even called "horizontal waterwheels".However, some sources mention turbines with both vertical and horizontal axes.N.F. Burnham, an American turbine manufacturer, patented numerous improved designs during the second half of the 19th century.His turbines are more efficient than Jonval's, especially at some gates, and have fewer maintenance issues.

Pelton wheel 

The Pelton turbine or Pelton turbine is a type of impulsive water turbine invented by American inventor Lester Allan Pelton in the 1870s.Impact bucket wheels extract energy from the momentum of flowing water,rather than relying on the water's own weight like traditional salvage water wheels.Many early variants of the impulse turbine existed, but they were less efficient than Pelton's design. The water leaving these wheels usually still has a high velocity, taking a lot of the kinetic energy away from the wheels.The geometry of the Pelton paddle is such that when the rim is running at half the speed of the water jet, the water leaves the wheel at very little speed; thus his design extracts almost all of the water's pulse energy this results in a very efficient turbine.

Applications

The Pelton wheel is the turbine of choice for hydroelectric power where the available water source has a relatively high head at low flow rates. Pelton wheels come in a variety of sizes.In hydroelectric power plants there are multi-ton percussion-type impact wheels mounted on vertical oil-cushioned bearings.The largest unit  the Bieudron hydroelectric power station at the Grande Dixence dam complex in Switzerland  exceeds 400 MW.The smallest Pelton wheels are only a few inches wide and can be used to harvest energy from mountain streams that flow several gallons per minute.Some of these systems use household plumbing fixtures for water delivery.These small units are recommended for water heads of 30 meters (100 feet) or more to produce significant power levels.Pelton wheels operate best at heads of 15-1,800 m (50-5,910 ft), depending on current and design, but there is no theoretical limit.