Steam Turbines :: essays research papers

Steam TurbinesThe invention of the water turbine was so successful that eventually,the idea came about for extracting power from move. Steam has one great favour over water-it expands in volume with tremendous velocity. To be themost effective, a steam clean turbine must run at a very high speed. No wheel madecan revolve at any speed approaching the velocity that a steam turbine can. Byutilizing the kinetic dexterity of steam flow, the turbine could achieve a higherefficiency. As a result, the steam turbine has supplanted the reciprocatingengine as a prime mover in large electricity-generating plants and is also employas a means of jet propulsion.The action of the steam turbine is based on the thermodynamic principlethat when a vapor is allowed to expand, its temperature drops. In turn, itsinternal energy is decreased. This reduction in internal energy is transformedinto mechanical energy in the form of an acceleration of the particles of vapor.The transformation that occurs, pr ovides a large amount of getable work energy.The essential parts of all steam turbines consist of nozzles or jetsthrough which the steam can flow and expand. Thus, the temperature drops, andkinetic energy is gained. In addition, on that point are blades, on which high pressuresteam is exerted. Stationary blades shift the steam onto rotating blades, whichprovide power. Also, turbines are equipped with wheels or drums where theblades are mounted. A radiation therapy for these wheels or drums is also a basic component,as well as an outer casing that confines the steam to the area of the turbineproper. In order to expeditiously use this contraption, it is necessary to stand anumber of stages. In each of these stages, a small amount of thermal energy isconverted to kinetic energy. If the completed conversion of energy took place atonce, the rotative speed of the turbine wheel would be way too excessive.Steam turbines are really quite simple machines, that have only onemajor moving p art, the rotor. However, auxiliary equipment is necessary fortheir operation. Journal bearings support the shaft, and an oil system provideslubrication to these bearings. A special seal system prevents steam from