Liquid water at 60 bar and 250C passes through an adiabatic expansion valve, emerging at a pressure Pf and a temperature Tf. If Pf is low enough, some of the liquid will evaporate.

a. If Pf = 1.0 bar, determine the temperature of the final mixture (Tf) and the fraction of the liquid feed that evaporates (yv) by writing an energy balance about the valve and neglecting kinetic energy changes.

b. If you did account for kinetic energy changes in part a., how would the calculated outlet temperature compare with the value you determined? What about the value of yv?

c. What is the value of Pf above which no evaporation would occur?

d. Sketch the approximate shape of a plot of Tf vs Pf and yv versus Pf for 1 bar < Pf < 60 bar. Briefly explain your reasoning.