A schematic of a combined refrigeration cycle and a portion of a steam power cycle is shown in the figure below. In the power cycle, steam (water) with a mass flow rate m, enters the turbine at state 1. A portion of the steam (rm,) exits the turbine at state 2 before passing through the mixing chamber. The remainder (m, - 3 kg/s) exits the turbine at state 3 and then enters a heat exchanger where it is cooled by the refrigeration cycle. The water leaves the heat exchanger at state 4 as a saturated liquid and then is pumped up to the mixing chamber pressure. R-134a with a mass flow rate of ṁg is used in the refrigeration cycle to provide cooling to the water in the heat exchanger. Properties at each state are given in the figure below. Assume that the compressor, turbine, pump, mixing chamber, throttling valve and outer walls of the heat exchanger are well insulated and neglect changes in potential and kinetic energy across all devices. a) Determine the pump work, Wp. b) Determine the work output of the turbine, Wr. c) Determine the heat transfer from the water to the R-134a in the heat exchanger, QHe-

A schematic of a combined refrigeration cycle and a portion of a steam power cycle is shown in the figure below. In the power cycle, steam (water) with a mass flow rate m, enters the turbine at state 1. A portion of the steam (rm,) exits the turbine at state 2 before passing through the mixing chamber. The remainder (m, - 3 kg/s) exits the turbine at state 3 and then enters a heat exchanger where it is cooled by the refrigeration cycle. The water leaves the heat exchanger at state 4 as a saturated liquid and then is pumped up to the mixing chamber pressure. R-134a with a mass flow rate of ṁg is used in the refrigeration cycle to provide cooling to the water in the heat exchanger. Properties at each state are given in the figure below. Assume that the compressor, turbine, pump, mixing chamber, throttling valve and outer walls of the heat exchanger are well insulated and neglect changes in potential and kinetic energy across all devices. a) Determine the pump work, Wp. b) Determine the work output of the turbine, Wr. c) Determine the heat transfer from the water to the R-134a in the heat exchanger, QHe-

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 12RQ: Refrigerators currently being manufactured in the United States are using______as their refrigerant.

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