The use of two expansion valves allows regions of different levels of cooling in a fridge/freezer unit with use of only a single refrigeration cycle. The kitchen is at 25°C, the fridge at 5°C and the freezer at -1°C. The system uses R134a as the working fluid. Question 1. a) Draw the T-s diagram for the multistage diagram shown in figure 1. b) Calculate the required pressure drop in both expansion valves if the temperatures in the hat exchangers need to be 5°C offset from the regional temperature.

The use of two expansion valves allows regions of different levels of cooling in a fridge/freezer unit with use of only a single refrigeration cycle. The kitchen is at 25°C, the fridge at 5°C and the freezer at -1°C. The system uses R134a as the working fluid. Question 1. a) Draw the T-s diagram for the multistage diagram shown in figure 1. b) Calculate the required pressure drop in both expansion valves if the temperatures in the hat exchangers need to be 5°C offset from the regional temperature.

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Description: please help ExpansionvalveQLARKitchen airQHCondenserRefrigerator(6A (Alternative path)ExpansionvalveFreezerQLFCompressorFigure 1:Image source: Thermodynamics MASK2100 V23, Week 12 - Refrigeration CycleThe use of two expansion valves allows regions of

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

Chapter44: Geothermal Heat Pumps

Section: Chapter Questions

Problem 13RQ: If 14 gpm of water is flowing through an open-loop heat pump with a temperature difference of 7F,...

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If 14 gpm of water is flowing through an open-loop heat pump with a temperature difference of 7F, how much heat in Btu/h is being absorbed or rejected in the heat pump? Show all work and units.
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