Search results
Results from the WOW.Com Content Network
In 1827 the Frenchmen Real and Pichon patented and constructed a compound impulse turbine. [11] The first steam turbine-powered ship Turbinia: fastest in the world at that time. The modern steam turbine was invented in 1884 by Charles Parsons, whose first model was connected to a dynamo that generated 7.5 kilowatts (10.1 hp) of electricity. [12]
Fig-3: Schematic Diagram of Pressure compounded Impulse Turbine. The pressure compounded Impulse turbine is also called a Rateau turbine, after its inventor. This is used to solve the problem of high blade velocity in the single-stage impulse turbine. It consists of alternate rings of nozzles and turbine blades.
The exit steam from one turbine is made to enter the nozzle of the succeeding turbine. Each of the simple impulse turbines would then be termed a "stage" of the turbine. Each stage comprises its ring of nozzle and blades. The steam from the boiler passes through the first nozzle ring, where its pressure drops and velocity increases. [2]
A Pelton wheel is an impulse design. A Reaction Turbine Stage [1] Reaction Turbomachines operate by reacting to the flow of fluid through aerofoil shaped rotor and stator blades. The velocity of the fluid through the sets of blades increases slightly (as with a nozzle) as it passes from rotor to stator and vice versa.
The degree of reaction contributes to the stage efficiency and thus used as a design parameter. Stages having 50% degree of reaction are used where the pressure drop is equally shared by the stator and the rotor for a turbine. Figure 4. Velocity triangle for Degree of Reaction = 1/2 in a turbine
Curtis' turbine reached a lower efficiency than the Parsons' turbine. It was, however, much smaller and simpler in design, thus making it suitable for simple applications and mobile use (e.g.on steamships). Curtis spoke to various companies about his turbines, but met no interest until he met Edwin W. Rice of General Electric.
The Ljungström turbine (Ljungströmturbinen) is a steam turbine. It is also known as the STAL turbine, from the company name STAL ( Swedish : Svenska Turbinfabriks Aktiebolaget Ljungström ). The technology has had numerous uses since its conception, from power plants to vehicles as large as the supertanker Seawise Giant .
The steam passing through the last stage of turbine has a high velocity and a large moisture content. The liquid particles have lesser velocity than that of vapor particles; hence, the liquid particles obstruct the flow of vapor particles in the last stage of the turbine, and therefore, a part of kinetic energy of the steam is lost.