A vapor-compression refrigeration cycle uses R-134a in a heat pump format. The mass flow rate of the R-134a is 300 g/s, and the R-134a enters the compressor as a saturated vapor at –15°C and exits the...

A vapor-compression refrigeration cycle uses R-134a in a heat pump format. The mass flow rate of the R-134a is 300 g/s, and the R-134a enters the compressor as a saturated vapor at –15°C and exits the condenser as a saturated liquid at 30°C. The isentropic efficiency of the compressor is 0.80. Determine the rate at which heat is delivered to the warm space through the condenser and the coefficient of performance of the cycle as a heat pump for (a) the cycle employing a throttling valve, and (b) the cycle employing a turbine with an isentropic efficiency of 0.70 in place of the throttling valve.