A heat pump uses R-134a as the working fluid and operates on an ideal vapor-compression refrigeration cycle between 26 psia and 138 psia. Determine (on a per unit mass basis) (a) the amount of heat transferred from the refrigerated space, (b) the amount of heat rejected by the cycle, (c) the work input required by the compressor, (d) the quality at the exit of the throttle valve, and (e) and the COP.
A heat pump uses R-134a as the working fluid and operates on an ideal vapor-compression refrigeration...
A heat pump uses R-134a as the working fluid and operates on an ideal vapor-compression refrigeration cycle between 25 psia and 140 psia. Determine (on a per unit mass basis) the heat transfer rates, the power required, and the COP.
11-14 A refrigerator uses refrigerant-134a as the working fluid and operates on an ideal vapor-compression refrigeration cycle between 0.12 and 0.7 MPa. The mass flow rate of the refrigerant is 0.05 kg/s. Show the cycle on a T-s diagram with respect to saturation lines. Determine (a) the rate of heat removal from the refrigerated space and the power input to the compressor, (b) the rate of heat rejection to the environment, and (c) the coefficient of performance. Answers: (a) 7.41...
An ideal vapor-compression refrigerant cycle operates at steady state with Refrigerant 134a as the working fluid. Saturated vapor enters the compressor at -10°C, and saturated liquid leaves the condenser at 28°C. The mass flow rate of refrigerant is 5 kg/min. Determine (a) The compressor power, in kW (b) The refrigerating capacity, in tons. (c) The coefficient of performance. Sketch the system on a T-s diagram with full label. A vapor-compression heat pump with a heating capacity of 500 kJ/min is...
11-11 A refrigerator operates on the ideal vapor-compression refrigeration cycle and uses refrigerant-134a as the working fluid. The condenser operates at 1.6 MPa and the evaporator at -6oC. If an adiabatic, reversible expansion device were available and used to expand the liquid leaving the condenser, how much would the COP improve by using this device instead of the throttle device?
A two-stage compression refrigeration system with an adiabatic liquid-vapor separation unit uses refrigerant-134a as working fluid. The system operates the evaporator at 0.4 MPa, the condenser at 1.6 MPa, and the separator at 0.8 MPa. The compressors use 25 kW of power. Given that the refrigerant is saturated liquid at the inlet of each expansion valve and saturated vapor at the inlet of each compressor, and the compressors are isentropic: (0) show the process on a T-s diagram; ) calculate...
An ideal vapor-compression refrigeration cycle operates with refrigerant-134a as the working fluidto serve a 400 kW of cooling load. The pressure of condenser is kept at 1000 kPa and the temperate ofthe evaporator is 4oC. Determine(a) The power required (kW)(b) The COP
A heat pump operates on the ideal vapor compression refrigeration cycle with R-134a. The condenser pressure is 1.2 MPa and the specific enthalpy at the inlet to condenser is 279 kJ/kg. If the mass flow rate of the refrigerant is 0.193 kg/s, the rate of heat supply to the heated space is answer is 31.1 kw
(12 points) A refrigerator using refrigerant-134a as the working fluid operates on the vapor compression cycle. The cycle operates between 200 kPa and 1.2 MPa. The refrigerant flows through the cycle at a rate of 0.019 kg/s. The (actual) refrigerator has a compressor with an isentropic efficiency of 85%. The refrigerant enters the compressor slightly superheated by 56 C hint add this to the saturation temperature). The refrigerant leaves the condenser slightly subcooled by 1.9°C. What is the rate of...
In a vapor-compression refrigeration heat pump cycle with Refrigerant 134a as the working fluid provides heating at a rate of 15 kW to maintain a building at 20 °C year-round. During the heating mode in the winter, the outside temperature is 5 °C. It is also used for cooling in the summer when outside temperature is 34°C. Saturated vapor at 2.4 bar leaves the evaporator and superheated vapor at 8 bar leaves the compressor. There is no significant heat transfer...
In a vapor-compression refrigeration heat pump cycle with Refrigerant 134a as the working fluid provides heating at a rate of 15 kW to maintain a building at 20 °C year-round. During the heating mode in the winter, the outside temperature is 5 °C. It is also used for cooling in the summer when outside temperature is 34 °C. Saturated vapor at 2.4 bar leaves the evaporator and superheated vapor at 8 bar leaves the compressor. There is no significant heat...