Pressure Compounding Of Steam Turbines

In this method, a number of simple impulse turbine stages is arranged in series. Each of these simple Impulse turbines consists of one set of Nozzles ( F.N ) and one row of moving blades (M.B). The exhaust from each row of moving blades enters the succeeding set of nozzles. The steam from the boiler is passed through the nozzles and moving blades. The steam velocity increases when it passes through nozzles and pressure drops. The steam velocity decreases without much alteration in pressure as it flows over the moving blades. Finally, the pressure falls down to condenser pressure.

Both the variation in pressure and velocity will vary while the steam flows through fixed nozzle and moving blades. The pressure is reduced in each stage of nozzle rings and hence this is called Pressure compounding.

Examples of this type of turbines are Rateau turbine and Zoelly turbine.

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Mechinopedia For Mechanical Engineers

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