The working fluid of a liquid-vapor cycle is 1kg of R-134a (Hint: Use the R-134a thermodynamic tables.) The cycle operates between two pressures 100kPa and 1000kPa. Process A-B: An isobaric compression at the high pressure from a saturated vapor to a saturated liquid. • ProcessB-C: An iso-entropic process from the high pressure to the low pressure. Process C-D: An isobaric expansion at the low pressure. •Process D-A: An iso-entropic process from the low pressure to the high pressure. • a) Make a table of the temperature, pressure, volume, internal energy, enthalpy, entropy and quality factor (T, P, V, U, H, S & x) at the start of each process. b) Make a table of the change in internal energy, heat flow, work done, change in enthalpy, and change in S) during each leg of the cycle.AH, AU, Q, W, Aentropy (c) Draw a well-labeled T-S diagram (indicating lines of constant pressure and the saturation dome.) d) Calculate the coefficient of performance of the cycle

The working fluid of a liquid-vapor cycle is 1kg of R-134a (Hint: Use the R-134a thermodynamic tables.) The cycle operates between two pressures 100kPa and 1000kPa. Process A-B: An isobaric compression at the high pressure from a saturated vapor to a saturated liquid. • ProcessB-C: An iso-entropic process from the high pressure to the low pressure. Process C-D: An isobaric expansion at the low pressure. •Process D-A: An iso-entropic process from the low pressure to the high pressure. • a) Make a table of the temperature, pressure, volume, internal energy, enthalpy, entropy and quality factor (T, P, V, U, H, S & x) at the start of each process. b) Make a table of the change in internal energy, heat flow, work done, change in enthalpy, and change in S) during each leg of the cycle.AH, AU, Q, W, Aentropy (c) Draw a well-labeled T-S diagram (indicating lines of constant pressure and the saturation dome.) d) Calculate the coefficient of performance of the 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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