VÁLVULAS DE EXPANSÃO: Comparação da aplicação de válvulas de expansão eletrônica e termostática em sistemas frigoríficos

Abstract

This project has as a basic principle the study of a refrigeration system. Its goal is to make a comparison between two models of expansion valves, component responsible for falling temperature and pressure in the system. From its evolution, this device has been being improved and ranges from exclusively mechanical models to the most current model, which is composed of electronic part device, able to read system variations and modular so that it is possible to obtain the higher system yield as a whole. Each model of this device, regardless of whether thermostatic or electronic should be scaled in coherence with the rest of the circuit, so the expansion device relies on the opening and closing of the valve needle, when electronic, this component checks the presence or not of liquid returning to the compressor, and closes the valve, decreasing the amount of fluid that will be injected into the evaporator, making the system fully efficient. The results show that the rate of variation when using the electronic expansion valve is considerably lower, avoiding sudden variations in the system and keeping it in perfect working condition.