THE EXPERIMETAL INVESTIGATION OF EVAPORATOR’S CONDITION ON PERFORMANCE OF REFRIGERATION SYSTEMS

Abstract

Due to the heat and mass transfer characteristics, the cooling and dehumidifying processes of evaporator are complex. In this sense, the present paper details the heat and mass transfer coefficients of moist air over surfaces for different cooling mode: dry, wet and partially wet. A modeling of the classical evaporator was reviewed by using finned surfaces wavy correlations for air-side. The mode of cooling was determined through a latent air–side convective heat transfer coefficient by correlating the experimental data with the model. In the literature have values of fouling factor for oil-bearing refrigerant and a fouling factor for air side coefficients for evaporator in operation for five years. The results have shown new values for these coefficients for evaporator in operation for eight years identifying a reduction of the nominal refrigeration capacity.