Thermal analysis of plate condensers in presence of flow maldistribution using refrigerant R134a

Flow maldistribution in plate heat exchangers causes deterioration of both thermal and hydraulic performance. The situation becomes more complicated for two phase flows during condensation where uneven distribution of the liquid to the channels reduces heat transfer due to high liquid flooding. The present study evaluates the thermal performance of falling film plate condensers with flow maldistribution from port to channel considering the heat transfer coefficient inside the channels as a function of channel flow rate. A generalized mathematical model has been developed to investigate the effect of maldistribution on the thermal performance as well as the exit vapor quality of a refrigerant, namely R-134a. A wide range of parameters are studied and these show the effects of the mass flow rate ratio of cold fluid (water) and two-phase refrigerant fluid, flow configuration, number of channels and correlation for the heat transfer coefficient. The analysis presented here also suggests an improved method for heat transfer data analysis for plate condensers. Copyright