Análisis comparativo del rendimiento en una bomba de calor utilizando una válvula de expansión termostática y una electrónica mediante el uso del refrigerante R600a.

Abstract

This document deals with the analysis of the performance of a direct-expansion solar-assisted heat pump by evaluating a thermostatic expansion valve and an electronic expansion valve as the best options for expansion devices, the components of said pump are: a compressor of 1/6 hp, expansion device, a copper condenser, and a collector plate painted black to increase the absorptivity. After an environmental analysis, the most eco-friendly refrigerant is used, this refrigerant is the R600a, refrigerant from which its thermodynamic properties have been obtained through the EES software. The tests have been tabulated with data obtained during a month and a half, every five minutes performing five tests a day evaluating different weather situations. The maximum temperature of the water that reached in the tests is 50 ° C, the time of heating of the water, as well as the efficiency of this, depend on the climatic condition that you have and the type of expansion device, for example, in days cleared at 12h00 with the thermostatic expansion valve an average radiation of 543.7 W · m-2 and an ambient temperature of 19.7 ° C was reached, the equipment took 80 minutes to reach the temperature of 50 ° C. The efficiency of the system was in an optimal range between 2.43 and 5.58. Finally, with the electronic expansion valve an average radiation of 500.76 W · m-2 and an ambient temperature of 18.7 ° C was reached, the equipment took 50 minutes to reach the water temperature of 50 ° C. The efficiency of the system was in the range of 3.83 and 7.48. The implementation of the heat pump system aims to reduce the CO2 emissions produced by traditional water heating equipment, in addition to the selected refrigerant can reduce the damage to the ozone layer and reduce the emission of gases that cause the greenhouse effect. To obtain data such as radiation, ambient temperature and wind speed, a meteorological station and a temperature measurement device (pyrometer) were used. The graphs that contain the experimental results were elaborated in the MATLAB program.