CHE Thermodynamics_TUD
Chapter 5 Homework 2
Winter 2009
5.3 Propane at 350 oC and 600 cm3/mol is expanded in an isentropic turbine. The exhaust pressure is
atmospheric. What is the exhaust temperature? PvT behavior has been fit to the van der Waals
equation of state with
a = 92 x 105 [(atm cm6)/mol2]
b = 91 [cm3/mol]
Solve this using T and v as the independent variables, that is: s = s(T,v).
5.4 Ethylene is liquefied by a Joule-Thomson expansion. It enters the throttling process at 50 bar and 0
o
C and leaves at 10 bar. What is the fraction of the inlet stream that is liquefied? At what
temperature does the ethylene leave the valve? Attached is literature information found for ethylene
from “Thermodynamic Properties in SI”, W.C. Reynolds, Stanford University Mechanical
Engineering, Stanford, CA (1979).
1/1