Q3. Consider a refrigerator operating on an ideal vapour-compression refrigeration cycle betweenpressures of 0.8435 and 8.8672 bar and using R134a as the working fluid. Pressure drops in theevaporator and condenser may be neglected.(a). Sketch the cycle on the T-s diagram.ii. Sketch the cycle on the p-h diagram including labels for the components on the diagram, heatand work transfers, as well as the pressure values given above.i. Name three assumptions made about the compression process in an ideal vapourcompression refrigeration cycle.(b)i Determine the specific enthalpy before and after the evaporator (kl/kg).i. Determine the refrigerant duty (Q.) if the mass flow rate of the refrigerant is 15.3 x 10 kg/s.i. Determine the specific enthalpy after the compressor (kl/kg).iv.Determine the compressor power and the coefficient of performance.

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Q3. Consider a refrigerator operating on an ideal vapour-compression refrigeration cycle between pressures of 0.8435 and 8.8672 bar and using R134a as the working fluid. Pressure drops in the evaporator and condenser may be neglected. (a) . Sketch the cycle on the T-s diagram. Sketch the cycle on the p-h diagram including labels for the components on the diagram, heat and work transfers, as well as the pressure values given above. Name three assumptions made about the compression process in an ideal vapour compression refrigeration cycle.

Q3. Consider a refrigerator operating on an ideal vapour-compression refrigeration cycle between pressures of 0.8435 and 8.8672 bar and using R134a as the working fluid. Pressure drops in the evaporator and condenser may be neglected. (a) . Sketch the cycle on the T-s diagram. Sketch the cycle on the p-h diagram including labels for the components on the diagram, heat and work transfers, as well as the pressure values given above. Name three assumptions made about the compression process in an ideal vapour compression refrigeration cycle.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 15RQ: Why is two-stage compression popular for extra-low-temperature refrigeration systems?

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