Fresh air at 3200 cfm, 41oC and 30% rh is mixed with recirculated air at 24oC...
Fresh air at 3200 cfm, 41oC and 30% rh is mixed with recirculated air at 24oC and 50% rh. The mixed air stream temperature is 32oC. The mixed air stream is then cooled, dehumidified and reheated to 16oC and 40% rh.
The cooling is provided with a multi-stage vapor compression refrigeration system using R717 as the working fluid. The evaporator temperature is 12oC less than the air temperature leaving the cooling coil and the condenser temperature is 12oC higher than the fresh air temperature. The intermediate pressure is selected such that the temperature in the flash tank is the average of the evaporator and condenser temperatures. Assume that the refrigeration system is ideal except for the compressor efficiencies, which are 67%.
Determine:
- The cooling load, in kW.
- The volume flow rate of condensate removed in the cooling coil, in L/min.
- The heating load, in kW.
- The three pressures for the two-stage vapor compression refrigeration cycle, in bar.
- The total power input to the compressors, in kW.
- The rate of heat rejection from the condenser, in kW.
- The COP of the system.
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Fresh air at 3200 cfm, 41oC and 30% rh is mixed with
recirculated air at 24oC...
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