A refrigeration system is being designed to maintain a small frozen storage room at -5°C. The required cooling rate is 50 kW. Waste heat from the refrigeration system will be rejected to the outdoor air at 35°C. The system will be designed such that the evaporation temperature will be either -10°C or -20°C, and the condensing temperature will be either 40°C or 50°C. UAcond For the 4 possible combinations of evaporator and condenser Tcond temperatures: Apply the "rule of thumb" to estimate the cooling COP Tr Ecomp Estimate the required "size" of the evaporator heat exchange surface, UAevap Practical Refrig (W/°C) T. Estimate the required "size" of the condenser heat exchange surface, UA cond (W/°C) Tevap UAevap Show your work for Scenario A and complete the following table: Design Scenario Tevap (°C) Tcond (°C) СОР. UA evap (W/°C) UA cond (W/°C) А -10 40 В -20 40 -10 50 D -20 50

A refrigeration system is being designed to maintain a small frozen storage room at -5°C. The required cooling rate is 50 kW. Waste heat from the refrigeration system will be rejected to the outdoor air at 35°C. The system will be designed such that the evaporation temperature will be either -10°C or -20°C, and the condensing temperature will be either 40°C or 50°C. UAcond For the 4 possible combinations of evaporator and condenser Tcond temperatures: Apply the "rule of thumb" to estimate the cooling COP Tr Ecomp Estimate the required "size" of the evaporator heat exchange surface, UAevap Practical Refrig (W/°C) T. Estimate the required "size" of the condenser heat exchange surface, UA cond (W/°C) Tevap UAevap Show your work for Scenario A and complete the following table: Design Scenario Tevap (°C) Tcond (°C) СОР. UA evap (W/°C) UA cond (W/°C) А -10 40 В -20 40 -10 50 D -20 50

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

Chapter47: High-pressure, Low-pressure, And Absorption Chilled-water Systems

Section: Chapter Questions

Problem 13RQ: The subcooling temperature in a condenser can be measured by taking the difference between the A....

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