Engineering, 23.08.2019 01:30 mirandac9394

Arefrigeration plant operates in pretoria on refrigerant r134a at an evaporator pressure of 105kpa (gauge) and a condensing pressure of 920 kpa (gauge). there is a sub-cooling of 3k with a superheat of the gas entering the compressor of 8k. the compressor is a four-cylinder reciprocating compressor with a bore of 67mm and a stroke of 57mm with an estimated capacity of 35kw. the compressor is directly coupled to an electric motor running at 1470rev/min and a power consumption of 19,5 kw. calculate: 1. the clearance volume efficiency if the compressor clearance is 3,6% 2. the actual volumetric efficiency 3. the compression efficiency when the mechanical efficiency is 85% and the motor efficiency 90%.

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Arefrigeration plant operates in pretoria on refrigerant r134a at an evaporator pressure of 105kpa (...