A heat pump operating with R-134a is used to maintain an indoor temperature of 21°C using...
A heat pump operating with R-134a is used to maintain an indoor temperature of 21°C using heat from the bottom of a lake that stays at 2°C. Assume an 80% efficient compressor. If the heat pump supplies 100 kW of energy to the building, calculate the required mass flow rate and COP for the heat pump. Calculate a few data points to plot the effect of a 10°C temperature range at the cold side on required mass flow rate and COP. Repeat this for any two different refrigerants. Note that the indoor and water temperatures realistically do not match the condenser and evaporator temperatures. Explain your choices for condenser and evaporator temperatures used in the calculations.
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A heat pump operating with R-134a is used to maintain an indoor
temperature of 21°C using...
Problem #3 Refrigerant R-134a enters the condenser of a heat pump at 1000 kPa and 80°C...
Problem #3 Refrigerant R-134a enters the condenser of a heat pump at 1000 kPa and 80°C at a rate of 0.025 kg/s and leaves at 1000 kPa as saturated liquid. If the compressor consumes 2 kW of power, determine: a) The COP of the heat pump (as heating device). b) The rate of heat absorption from the outside air. тан Condenser Throttling valve Compressor Evaporator To
An ideal vapor-compression heat pump cycle using R-134a is used to heat a house. The inside...
An ideal vapor-compression heat pump cycle using R-134a is used to heat a house. The inside temperature is 22 ℃; the outside temperature is 0 ℃ Saturated vapor at 2.2 bar enters the compressor, and saturated liquid leaves the condenser at 3 ba. The mass ow rate is 0.2 kg/s. Detemine: a the power iput to the compressor (in kw) b. the coefficient of performance c. the coefficient of performance if the system were used as a refrigeration cycle d....
A heat pump with refrigerant-134a as the working fluid is used to keep a space at 25°C by |absorbing heat from geotherm...
A heat pump with refrigerant-134a as the working fluid is used to keep a space at 25°C by |absorbing heat from geothermal water that enters the evaporator at 50°C at a rate of 0.046 kg/s and leaves at 40°C. The refrigerant enters the evaporator at 20°C with a quality 23 percent and leaves at the inlet pressure as saturated vapor. The refrigerant loses305 W o heat to the surroundings as it flows through the compressor and the refrigerant leaves the...
QUESTION 1 A heat pump with refrigerant-134a as the working fluid is used to keep a...
QUESTION 1 A heat pump with refrigerant-134a as the working fluid is used to keep a space at 25°C by absorbing heat from geothermal water that enters the evaporator at 50°C at a rate of 0.065 kg/s and leaves at 40°C. The refrigerant enters the evaporator at 20°C with a quality of 23 percent and leaves at the inlet pressure as saturated vapor. The refrigerant loses 300 W of heat to the surroundings as it flows through the compressor and...
6. An office building requires a heat transfer rate of 20 kW to maintain the inside temperature a...
6. An office building requires a heat transfer rate of 20 kW to maintain the inside temperature at 21°C when the outside temperature is 0°C. A vapor-compression heat pump with Refrigerant 134a as the working fluid is to be used to provide the necessary heating. The compressor operates adiabatically with an isentropic efficiency of 82%. Specify appropriate evaporator and condenser pressures of a cycle for this purpose assuming Δ1cond-Al evap-10°C, as shown below. The states are numbered as shown below....
In a vapor-compression refrigeration heat pump cycle with Refrigerant 134a as the working fluid provides heating...
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...
In a vapor-compression refrigeration heat pump cycle with Refrigerant 134a as the working fluid provides heating...
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...
In a vapor-compression refrigeration heat pump cycle with Refrigerant 134a as the working fluid provides heating...
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...
Figure 12.1 is a schematic of a heat pump operating at steady state with R-134a as...
Figure 12.1 is a schematic of a heat pump operating at steady state with R-134a as the working fluid. The mass flow rate of the refrigerant is 7 kg/min, and the power input to the compressor is 5.17 kW. Determine a) The coefficient of performance, y b) If the valve were replaced by a turbine, what would be the maximum power generated by the turbine c) Based on your answer to b) would you recommend the replacement of a throttle...
A house uses a heat pump to maintain the indoor temperature at 22 C on a...
A house uses a heat pump to maintain the indoor temperature at 22 C on a cold winter day when the outside temperature is -10 C. On this day, the house receives heat from the heat pump at a rate of 24 kW. Is it possible for this heat pump to operate at 2.5 kW? Justify your answer.
Problem #3 Refrigerant R-134a enters the condenser of a heat pump at 1000 kPa and 80°C at a rate of 0.025 kg/s and leaves at 1000 kPa as saturated liquid. If the compressor consumes 2 kW of power, determine: a) The COP of the heat pump (as heating device). b) The rate of heat absorption from the outside air. тан Condenser Throttling valve Compressor Evaporator To
An ideal vapor-compression heat pump cycle using R-134a is used to heat a house. The inside temperature is 22 ℃; the outside temperature is 0 ℃ Saturated vapor at 2.2 bar enters the compressor, and saturated liquid leaves the condenser at 3 ba. The mass ow rate is 0.2 kg/s. Detemine: a the power iput to the compressor (in kw) b. the coefficient of performance c. the coefficient of performance if the system were used as a refrigeration cycle d....
QUESTION 1 A heat pump with refrigerant-134a as the working fluid is used to keep a space at 25°C by absorbing heat from geothermal water that enters the evaporator at 50°C at a rate of 0.065 kg/s and leaves at 40°C. The refrigerant enters the evaporator at 20°C with a quality of 23 percent and leaves at the inlet pressure as saturated vapor. The refrigerant loses 300 W of heat to the surroundings as it flows through the compressor and...
6. An office building requires a heat transfer rate of 20 kW to maintain the inside temperature at 21°C when the outside temperature is 0°C. A vapor-compression heat pump with Refrigerant 134a as the working fluid is to be used to provide the necessary heating. The compressor operates adiabatically with an isentropic efficiency of 82%. Specify appropriate evaporator and condenser pressures of a cycle for this purpose assuming Δ1cond-Al evap-10°C, as shown below. The states are numbered as shown below....
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...
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...
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...
Figure 12.1 is a schematic of a heat pump operating at steady state with R-134a as the working fluid. The mass flow rate of the refrigerant is 7 kg/min, and the power input to the compressor is 5.17 kW. Determine a) The coefficient of performance, y b) If the valve were replaced by a turbine, what would be the maximum power generated by the turbine c) Based on your answer to b) would you recommend the replacement of a throttle...
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