Refrigerant-134a enters the condenser of a residential heat pump at 900 kPa and 65oC at a...

Refrigerant-134a enters the condenser of a residential heat pump at 900 kPa and 65^oC at a rate of 0.018 kg/s and leaves at 750 kPa subcooled by 2^oC. The refrigerant enters the compressor at 200 kPa superheated by 3^oC. Determine (a) the isentropic efficiency of the compressor in decimal (up to two decimals), (b) the rate of heat supplied to the heated room, and (c) the COP of the heat pump. Also determine (d) the COP if this heat pump operated on the ideal vapour compression cycle between the pressure limits of 200 and 900 kPa

Expert Solution

samet mamat answered 2 years ago

Refrigerant-134a enters an adiabatic compressor as saturated vapor at 160 kPa at a rate of 2.8...

Refrigerant-134a enters an adiabatic compressor as saturated vapor at 160 kPa at a rate of 2.8 m3/min and is compressed to a pressure of 900 kPa. Determine the minimum power that must be supplied to the compressor. Use the tables for R-134a. The minimum power that must be supplied to the compressor

Refrigerant R-134a enters the compressor of a refrigeration machine at 140 kPa pressure and -10 °...

Refrigerant R-134a enters the compressor of a refrigeration machine at 140 kPa pressure and -10 ° C temperature and exits at 1 MPa pressure. The volumetric flow of the refrigerant entering the compressor is 0.23 m3 / minute. The refrigerant enters the throttling valve at 0.95 MPa pressure and 30 ° C, exiting the evaporator as saturated steam at -18 ° C. The adiabatic efficiency of the compressor is 78%. Show the cycle in the T-s diagram. In addition, a)...

Saturated liquid refrigerant R-134a is throttled from 900 to 90 kPa at a rate of 0.32...

Saturated liquid refrigerant R-134a is throttled from 900 to 90 kPa at a rate of 0.32 kg/s. What is the rate of entropy generation for this throttling process? kW/K

Refrigerant 134a is the working fluid in a vapor-compression heat pump system with a heating capacity...

Refrigerant 134a is the working fluid in a vapor-compression heat pump system with a heating capacity of 60,000 Btu/h. The condenser operates at 180 lbf/in.2, and the evaporator temperature is 0°F. The refrigerant is a saturated vapor at the evaporator exit and a liquid at 110°F at the condenser exit. Pressure drops in the flows through the evaporator and condenser are negligible. The compression process is adiabatic, and the temperature at the compressor exit is 180°F. Determine (a) the mass...

Refrigerant 134a is the working fluid in a vapor-compression heat pump that provides 35 kW to...

Refrigerant 134a is the working fluid in a vapor-compression heat pump that provides 35 kW to heat a dwelling on a day when the outside temperature is below freezing. Saturated vapor enters the compressor at 2.1 bar, and saturated liquid exits the condenser, which operates at 8 bar. Determine for an isentropic compressor efficiency of 75%: (a) the refrigerant mass flow rate, in kg/s. (b) the magnitude of the compressor power, in kW. (c) the coefficient of performance.

Refrigerant 134a enters a horizontal pipe operating at steady state at 40°C, 300 kPa, and a...

Refrigerant 134a enters a horizontal pipe operating at steady state at 40°C, 300 kPa, and a velocity of 25 m/s. At the exit, the temperature is 70°C and the pressure is 240 kPa. The pipe diameter is 0.01 m. Determine: (a) the mass flow rate of the refrigerant, in kg/s, (b) the velocity at the exit, in m/s, and (c) the rate of heat transfer between the pipe and its surroundings, in kW.

Refrigerant R134a is entering a condenser and is being cooled by water. The refrigerant enters the...

Refrigerant R134a is entering a condenser and is being cooled by water. The refrigerant enters the condenser with a mass flow rate of 6 kg/min at 1 MPa and 70 0C and leaves at 35 0C. The cooling water enters at 300 KPa and 15 0C and leaves at 25 0C. Neglecting any pressure drop, determine: The mass flow rate of the cooling water The heat transfer rate from the refrigerant to the water. The rate of entropy production within...

For an ideal vapor-compression heat pump cycle, refrigerant 134a is used to provide 35 kW of...

For an ideal vapor-compression heat pump cycle, refrigerant 134a is used to provide 35 kW of heat to a building. Saturated vapor enters the compressor at 1.6 bar and saturated liquid exits the condenser which operates at 8 bar. What is (a) the mass flow rate of the refrigerant, and (b) the COP?

Refrigerant 134a in a cylinder-piston assembly is at 240 kPa with a quality 15% and then...

Refrigerant 134a in a cylinder-piston assembly is at 240 kPa with a quality 15% and then as a result of heat added the quality increases to 45%, what is the change in volume per one unit of mass (m3/kg)? The piston is assumed to move freely but it is sealed tight that does not allow mass exchange.

purpose of the condenser in a refrigeration system? a) rejects heat from refrigerant b)absorbs heat into...

purpose of the condenser in a refrigeration system? a) rejects heat from refrigerant b)absorbs heat into the refrigerant c) rejects heat from the condensing medium d) increases pressureand temp of the refrigerant

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