EXPERIMENTAL ANALYSIS OF THE AIR DEFROST PROCESS IN AN INDUSTRIAL COOLING SYSTEM

Year 2020, Issue: 045, 143 - 157, 31.12.2020

Süleyman Erten Meltem Koşan Furkan İşgen Mustafa Aktaş

Abstract

Keeping product temperatures homogeneous is an important problem in defrosted industrial coolers. In this study, it is aimed to obtain findings that will shed light on researchers and producers by analyzing the defrosting process of the industrial cooler. For these reasons, the system was designed using R290 (propane), a new generation refrigerant with a single evaporator, double condenser and double compressor, in order to ensure homogeneous cooling. By keeping the cooled products in the range of – 1 ℃ and +5 ℃ as required by the standard, during the experiment, temperature-pressure measurements of the refrigerated products and cooling system equipment were taken from certain points every minute and test data were recorded. The average temperature and relative humidity values measured minute of the environment where the experimental setup is located was calculated as 25℃ ±1℃ and 60%±0.02%, respectively. During the experiment, eight defrost operations were performed, and it was observed that the average temperature values taken from the products during the 24 hours during defrosting changed to 3.07℃. During the experiment, the highest and lowest temperatures of the cooled products were measured as 4.22℃ and 2.02℃. Increased product temperatures and cooling stopped during defrosting increased the power consumption in the system. In order to observe the effect of the power consumption on system performance, COP values after each defrost time were calculated as 2.31, 2.30, 2.29, 2.60, 3.36, 3.29, 3.30, 3.49, respectively. When the defrost process of cooling system analyzed, it was seen that the products were successfully cooled at desired temperature ranges in the scope of TS EN ISO 23953-2.

Keywords

Defrost, Industrial Cooling, Efficiency, Heat Pump

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