Thermodynamic properties of superheated and supercritical steam

An existing formulation for steam properties is due to Irvine and Liley. Th eir equations are convenient to program and do not require excessive comput ational time to produce results. The properties computed from these equatio ns compare favourably with standard data. An additional advantage of these equations is that they follow prescribed theoretical trends by reducing to perfect-gas behaviour away from the saturation dome. However, a difficulty with these equations is that, at pressures above 10 MPa and close to the sa turation dome, unacceptably large errors (above 10%) are produced. These eq uations are examined in the present work with a view towards enhancing thei r range of application through the use of additional functions. It is shown that the errors may be reduced to within 1% over the entire range of press ures (both sub-critical and super-critical pressures) required in steam-pla nt calculations. (C) 2001 Published by Elsevier Science Ltd. All rights res erved.