How Do You Calculate Steam Turbine Efficiencies?
Steam turbines are used to produce electricity as well as to power large ships. Steam turbines have several advantages over internal combustion-type engines. They have virtually no friction between moving mechanical parts, although there is friction between steam and turbine blades, and steam turbines are designed to run most efficiently at a stable, continuous loading factor. The straightforward path to calculating steam turbine efficiencies is to compare the useful energy being produced by the turbine to the energy that is being supplied to it by the boiler. Define the steam turbine application. In this example, two identical steam turbines drive two ship propellers on a large military vessel. Each turbine supplies 25,000-shaft-horsepower to a reduction gearbox to drive its propeller. If you know it requires 305,906-pounds/hour (lb/hr) of superheated 1,200-psia (pounds per square inch absolute) steam at 1,100 degrees Fahrenheit (deg F) to power each turbine and the spent saturated st
