Rankine Cycle: Summary

The answers to the ConcepTests are given below and will open in a separate window. 
Key points from this module:
  • In a Rankine cycle, heat is added at high temperatures in a boiler to create superheated steam at high pressure.
  • A fraction of the heat input to a Rankine cycle is converted to work in a turbine, and the rest is discarded at low temperature (typically to a river, lake, or cooling tower).
  • The exit enthalpy from an irreversible turbine is higher than that from a reversible turbine.
  • The objective of a Rankine cycle is to convert high temperature heat into work efficiently.
From studying this module, you should now be able to:
  • Apply the first law (and, where appropriate, account for efficiencies using the second law) to the boiler, condenser, turbine, and liquid pump in a Rankine cycle.
  • Calculate the work generated from a Rankine cycle.
  • Sketch a Rankine cycle on a T- S diagram and sketch how the turbine path changes when the turbine is irreversible.
  • Draw a Rankine cycle on a pressure versus enthalpy diagram.
  • Calculate the thermodynamic efficiency for a Rankine cycle.


Prepared by John L. Falconer, Department of Chemical and Biological Engineering, University of Colorado Boulder