4.1 A Refrigerant-22 plant operating at 0 °F evaporating temperature and 70 °F condensing temperature uses a reciprocating compressor having 4 percent clearance factor. Neglect valve pressure drops and superheating during the intake stroke. Under these conditions the plant produces 20 tons of refrigeration. (a) Calculate the capacity of the plant if the condensing temperature were to be increased to 100 °F. Assume that other conditions are the same and the compressor is operated at the same rpm. Assume a theoretical single-stage cycle but include the effect of compressor volumetric efficiency.
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To calculate h1, we need to use the refrigerant tables for Refrigerant-22 at 70F condensing temperature. From the tables, we find that h1 = 141.5 Btu/lb. To calculate h4, we need to use the refrigerant tables for Refrigerant-22 at 0F evaporating temperature. Show more…
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