Rankine Cycle
Rankine Cycle
The Rankine cycle, which produces work by expanding steam through a turbine, is shown on a pressure-enthalpy () diagram. High-pressure liquid water (1) enters a boiler where it is heated to saturation temperature (2) and vaporized, and it exits as superheated steam (3). The superheated steam is fed to a steam turbine, which expands the steam and generates mechanical work. The steam exits the turbine at a lower pressure and temperature (4); this steam is condensed to liquid water (5), which is compressed in a pump to high pressure (1).
P-H
You can vary the high pressure of the cycle (the pressure in the boiler and the pressure entering the turbine ()), the pressure exiting the turbine (), and the turbine efficiency , which is the ratio of work produced by the turbine to the work produced for a reversible turbine between the same inlet and exit pressures. The pathway for the reversible turbine is represented on the diagram by the dotted line.
P
3
P
4
η
P-H