Hot combustion gases, modeled as air behaving as an ideal gas, enter a turbine at 10 bar, 1500 K and exit at 1.97 bar and 900 K. If the power output of the turbine is 55.4 kW, determine the rate of heat transfer from the turbine to its surroundings, in kW.

The heat transfer from the turbine to the surrounding  Q = - 547.6 KW

Explanation:

Given data

Pressure at inlet = 10 bar

Temperature at inlet = 1500 K

Pressure at exit = 1.97 bar

Temperature at outlet = 900 K

Power output from the turbine = 55.4 KW

Apply steady flow energy equation for the turbine

-------- (1)

Put all the values in equation 1 we get,

Q =  1.005 ( 900 - 1500 ) + 55.4

Q = - 547.6 KW

This is the heat transfer from the turbine to the surrounding. here negative sign shows that heat is lost from the turbine to the surrounding.

energy can cross the boundaries of a closed system in the form of heat and mass

explanation: