Example
Using Mollier Chart, Superheated steam at 700 psia & 680°F is extended at constant entropy to 140 psia. Determine the change in enthalpy?
Solution:
By using the Mollier Chart, Place point 1 at the intersection of the 700 psia and the 680°F line. Study h = 1333 Btu/lbm.
Obey the entropy line down vertically to the 140 psia line and examine h = 1178 Btu/lbm.
?h = 1178 - 1333 = -155 Btu/lbm