A refrigeration system uses HFC-134A as the refrigerant. The desired evaporator temperature is 5oC and the condenser pressure is 1.2 MPa. The compressor efficiency is 75%.
a) Determine the coefficient of performance and the work required for 75 KJ of cooling.
b) How many tons of cooling does that correspond to?
A refrigeration system uses HFC-134A as the refrigerant. The desired evaporator temperature is 5oC and the...
A vapor compression refrigeration system operates at steady state with refrigerant 134a as the working fluid. Superheated vapor enters the compressor at 10 lbf/in2 , 0 oF. The liquid leaving the condenser is at 180 lbf/in2 , 100 oF. There is no significant pressure drop in the evaporator or condenser. For compressor efficiency of 83% and refrigeration capacity of 6 tons, determine (a) the compressor power input in horsepower, and (b) the coefficient of performance. A vapor compression refrigeration system...
A Refrigeration System Using R-134A In a refrigeration system, the refrigerant R-134A begins as saturated vapor at -15°(State 1). It then goes through a reversible adiabatic compressor to reach State 2. After flowing through the condenser (a heat exchanger), the refrigerant exits as saturated liquid at 70°C (State 3). It is then throttled by going through an expansion valve, to reach State 4. It finishes the cycle by going through another heat exchanger (the evaporator), to return to State 1....
Thermodynamics. No interpolation needed. Problem #3. Refrigerant 134a is the working fluid for vapor-compression refrigeration cycle. The evaporator temperature is 8°C and the condenser pressure is 12 bar. Saturated vapor enters the compressor and superheated vapor enters the condenser at 60°C and exits the condenser as saturated liquid. For a refrigeration capacity of 8 tons or 2.816 x104 J/s determine the following: (1) The refrigerant mass flow rate in kg/s; (2) The compressor isentropic efficiency [Hint: Interpolation is required); (3)...
An ideal vapor-compression refrigeration cycle with R-134a as the working fluid has an evaporator temperature of-15 °C and a condenser pressure of 12 bar. Saturated vapor enters the compressor, and saturated liquid exits the condenser. The mass flow rate of the refrigerant is 3.5 kg/min. Draw and label the cycle on a T-s diagram. What is the coefficient of performance? Ans. 2.98 What is the refrigerating capacity in tons? a. b. c.
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...
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 0.4Mpa, the condenser at 1.6Mpa and the separator at 0.8 Mpa. The compressors use 25kW of power. Given that the refrigerant is saturated liquid at the inlet of each compressor, and the compressors are isentropic: i) show the process on a T-s diagram, ii) calculate the rate of cooling provided by the evaporator, the COP of the heat...
In a heat pump operating according to the vapor compression refrigeration cycle, the refrigerant is R-134a. A water source of 11 °C is used to heat a house with a heating load of 17 kW. Refrigerant enters the compressor as saturated steam at 100 kPa pressure and rises at 1.6 MPa, 60 ° C. The temperature of the refrigerant at the outlet of the condenser is 30°C. a) The amount of heat at the beginning of the water, b) Compressor...
1) A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -30°C by rejecting its waste heat to cooling water that enters the condenser at 16 °C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 65°C and leaves at 42°C. The inlet state of the compressor is 60 kPa and -34°C and the compressor is estimated to gain a net heat of...
The system shown in the diagram provides 20tons of refrigeration. The system uses 134-a refrigerant. Using the data indicated on the diagram. A) find the minimum work requirement to the compressor B) compute the coefficient of performance C) determine the coefficient of performance of a Carnot refrigerator operating between the temperature limits of this system D) show the cycle on a properly labeled T-s diagram with respect to the saturation lines. (On the diagram, lets say compressor to the condenser...
R134a refrigerant In a vapor compression refrigeration system the following observations were noted. Condenser pressure 2 bar. Evaporator pressure 0.02 MPa. Sub-cooling 10°C. Super heating 20°C. Estimate the power consumed by compressor, heat absorbed in evaporator, heat rejected in condenser and coefficient of performance. Mark all given data in PH and TS diagram.