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In: Mechanical Engineering

A gas refrigeration cycle with a pressure ratio of 4.3 uses helium as the working fluid....

A gas refrigeration cycle with a pressure ratio of 4.3 uses helium as the working fluid. The temperature of the helium is 26°C at the compressor inlet and 50°C at the turbine inlet. Assuming isentropic efficiencies of 87 percent for both the turbine and the compressor, determine (a) the minimum temperature in the cycle, (b) the coefficient of performance, and (c) the mass flow rate of the helium for a refrigeration rate of 20 kW.

ans a)198.76 b)0.574 c)0.0564.

Can you show me the solution step by step please?

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