Turbines et al

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TURBINES et. al. A. Vania Politecnico di Milano, Dept. of Mechanical Engineering, Milan, Italy APPLIED MECHANICS – Prof. Andrea VANIA 2STEAM TURBINES A steam turbine is a type of continuous internal combustion engines. A steam turbine is a device that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Because the turbine generates rotary motion, it is particularly suited to be used to drive an electric generator. The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from the use of multiple stages in the expansion of the steam, which results in a closer approach to the ideal reversible expansion process. These turbines receive steam from a boiler and exhaust it to a condenser. The exhausted steam is at a pressure well below atmospheric, and is in a partially condensed state, typically of a quality near 90%. A boiler is a closed vessel in which water is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications like water heating, boiler-based power generation, sanitation, etc. . APPLIED MECHANICS – Prof. Andrea VANIA 3STEAM TURBINES Machine train diagram steam inlet (High Pressure) HP-IP steam turbine LP steam turbine HP IP LP HP: High pressure IP: Intermediate pressure LP: Low pressure shaft end connected to the generator rotor generator rotor APPLIED MECHANICS – Prof. Andrea VANIA 4GAS TURBINES A gas turbine is a type of continuous internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber or area, called a combustor, in between. The basic operation of the gas turbine is similar to that of the steam power…