Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
THERMODYNAMIC EVALUATION OF TWO PORTABLE COOLERS RUNNING WITH RECIPROCATING AND ROTARY COMPRESSORS
Submission Author:
Diego Marchi , SC , Brazil
Co-Authors:
Diego Marchi, Christian Hermes
Presenter: Diego Marchi
doi://10.26678/ABCM.COBEM2021.COB2021-1116
Abstract
Small-capacity refrigeration has got an increasing attention from the consumer market. In addition to the efficiency of electric equipment, the demand for compactness has also become a relevant requirement. Among the alternatives available to cool down small cabinets, mechanical vapor compression refrigeration remains prominent due to its satisfactory performance when compared to other cooling technologies. Compressor industries have invested in the development of compact and efficient products, exploring different compression principles for small-capacity applications, as is the case of rotary compressors. In this context, the objective of the present work is to assess the thermodynamic performance of a 38-liter portable vapor compression refrigeration system running with two different compressors designed for small-capacity applications: rotary and reciprocating. The compressors were installed in the refrigeration system and experimental tests were carried out at three different ambient temperatures (16, 25 and 32 °C) in order to obtain the key performance parameters for each compressor (e.g., power consumption, cooling capacity, internal air temperature, and the hot and cold end temperatures). Finally, thermodynamic analyses were conducted to account for the internal (e.g., viscous fluid flow) and external irreversibilities (finite temperature difference in the heat exchangers) by means of second law efficiencies, allowing for a comparison of the system performance running with both compressors in the same thermodynamic grounds. Albeit a refrigeration (second law) efficiency by 25% higher was observed for the reciprocating compressor, it provided a smaller cooling capacity and, therefore, led to a higher pull-down time.
Keywords
portable cooler, recriprocating compressor, rotary compressor, thermodynamic efficiency
