An air-conditioner which uses R-134a operates on the ideal vapor compression refrigeration cycle with a given compressor efficiency. --Given Values-- Evaporator Temperature: T1 (C) = 15 Condenser Temperature: T3 (C) = 32 Mass flow rate of refrigerant: mdot (kg/s) = 0.027 Compressor Efficiency: nc (%) = 77 a) Determine the specific enthalpy (kJ/kg) at the compressor inlet. Your Answer =255.6725 b) Determine the specific entropy (kJ/kg-K) at the compressor inlet Your Answer =0.912 c) Determine the specific enthalpy (kJ kg) at the compressor exit Your Answer =264.48 d) Determine the specific enthalpy (kJ/kg) at the condenser exit. Your Answer =94.39 e) Determine the specific enthalpy (kJ/kg) at the evaporator inlet. Your Answer =94.39 f) Determine the coefficient of performance for the system. Your Answer =1.45 g) Determine the cooling capacity (kW) of the system. Your Answer =4.35 h) Determine the power input (kW)to the compressor. Your Answer =3 ]Correct! Exact Answer= 255.67 +/- 1.0E-00 Correct! Exact Answer= 0.9120 +/- 3.7E-03 ] Incorrect. Correct! Exact Answer= 94.39 +/-5.3E-01 Correct! Exact Answer= 94.39 +/- 5.3E-01 | Incorrect. Correct! Exact Answer= 4.355 +/- 1.3E-02 Incorrect.

An air-conditioner which uses R-134a operates on the ideal vapor compression refrigeration cycle with a given compressor efficiency. --Given Values-- Evaporator Temperature: T1 (C) = 15 Condenser Temperature: T3 (C) = 32 Mass flow rate of refrigerant: mdot (kg/s) = 0.027 Compressor Efficiency: nc (%) = 77 a) Determine the specific enthalpy (kJ/kg) at the compressor inlet. Your Answer =255.6725 b) Determine the specific entropy (kJ/kg-K) at the compressor inlet Your Answer =0.912 c) Determine the specific enthalpy (kJ kg) at the compressor exit Your Answer =264.48 d) Determine the specific enthalpy (kJ/kg) at the condenser exit. Your Answer =94.39 e) Determine the specific enthalpy (kJ/kg) at the evaporator inlet. Your Answer =94.39 f) Determine the coefficient of performance for the system. Your Answer =1.45 g) Determine the cooling capacity (kW) of the system. Your Answer =4.35 h) Determine the power input (kW)to the compressor. Your Answer =3 ]Correct! Exact Answer= 255.67 +/- 1.0E-00 Correct! Exact Answer= 0.9120 +/- 3.7E-03 ] Incorrect. Correct! Exact Answer= 94.39 +/-5.3E-01 Correct! Exact Answer= 94.39 +/- 5.3E-01 | Incorrect. Correct! Exact Answer= 4.355 +/- 1.3E-02 Incorrect.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter41: Troubleshooting

Section: Chapter Questions

Problem 8RQ: When the outside ambient air temperature is 90F, the temperature of the condensing refrigerant in a...

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