Modares Mechanical Engineering

Modares Mechanical Engineering

An experimental investigation on the effect of ambient temperature on the performance of a vertical air curtain refrigerator

Document Type : Original Research

Authors
Elham Eskandari 1
Ebrahim Hajidavalloo 2
Mohammad Reza Saffarian 1
Saeed Mohaghegh 3
Omid Adibi 3
1 Shahid Chamran University of Ahvaz
2 Shahid Chamran university
3 Niroo research center
10.48311/mme.24.9.583
Abstract
Application of vertical air curtain refrigerators in commercial stores has gained popularity due to easy access of products by the customers. However, energy consumption of these refrigerators is approximately %50 higher than that of refrigerators with doors. This paper experimentally investigates the effect of ambient temperature variation on the performance of these refrigerators. Experimental measurements include parameters such as temperature, pressure, relative humidity, velocity, and power consumption in both air cycle and refrigeration cycle. Moreover, parameters such as compressor power, refrigeration effect, total load, coefficient of performance, pressure ratio, thermal entrainment coefficient, refrigeration capacity, volumetric and mass flow rates of air in the evaporator and condenser, refrigerant mass flow rate, condenser heat, air curtain thermal efficiency, Richardson number, Reynolds number, and deviation modulus under different ambient conditions were calculated. The experimental results show that the refrigeration performance is affected by ambient air temperature, which directly influence on the infiltration rate of ambient air into the refrigerator compartment and on the return air temperature to the evaporator. Therefore, the return air temperature is crucial indicator for assessing the efficiency of the refrigerator. With increasing ambient temperature, compressor power increases, while the refrigeration effect and COP decrease. The results also indicate that as ambient temperature rises, air curtain efficiency decreases somehow that temperature difference between front and rear of the shelves may reach up to 4.6°C. For every 1°C increase in ambient temperature, compressor power consumption increases by approximately %0.64, while refrigeration effect and COP decrease by %0.06 and %1.77, respectively
Keywords
Air-Curtain Refrigerator
Experimental Stud
energy consumption
coefficient of performance

Subjects

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Modares Mechanical Engineering
Volume 24, Issue 9
August 2024
Pages 583-595