8 Consider a turbocharger such as the one modeled in Problem

8. Consider a “turbocharger,” such as the one modeled in Problem 7-214. Which of the statements below is FALSE? (Select the best response.)

a) If the isentropic efficiency of the turbine is increased, the work input to the compressor will increase.

b) If the isentropic efficiency of the turbine is increased, the outlet temperature of the gases leaving the turbine will decrease.

c) If the isentropic efficiency of the turbine is increased, the outlet temperature of the gases leaving the compressor will decrease.

d) If the isentropic efficiency of the turbine is increased, the isentropic efficiency of the compressor will decrease.

Solution

a) False.. because when the work input of compressor will increase the isentropic efficiency of turbine will decrease.

b) True..if efficiency of turbine is increased, the outlet temperature of gases leaving the turbine will decrease.

c) True...efficiency of turbine increases implies that efficiency of compressor decreases, which implies that outlet temperature of gases leaving compressor will decrease.

d) True..as the overall efficiency of turbocharger is the product of isentropic efficiencies of turbine and compressor. So, as the isentropic efficiency of turbine is increased, the isentropic efficiency of compressor will decrease.