Simulação numérica da refrigeração por compressão de vapor aplicada a uma bancada didática

Abstract

Numerical simulations of the vapor compression refrigeration cycle are widely used in parametric studies, designs and point-of-operation optimizations. The models of heat exchangers are by zones, separating the zones of superheated steam, condensation and liquid subcooling in the condenser, and for the evaporator having the evaporation and superheated steam zones. In the compressor there is a semi-empirical model widely used in the literature, and for the expansion device, there is a capillary tube modeled by empirical correlations. The cycle was simulated by connecting the components in series by successive approximations, where the operational parameters are adjusted through repeated iterations until the simulation converges. The simulation is applied to a refrigeration bench and validated using experimental values. The parametric analyzes were of the variation of the condensation temperature and the variation of the ambient temperature. The models showed variations of less than 10 % between the experimental and the numerical, even when simulating the entire cycle with only the ambient temperature and the condensation pressure as input parameters.