Numerical study on the flow maldistribution characteristics of a plate heat exchanger

Flow maldistribution problem in the plate heat exchanger precludes the intended ideal performance. In this study, the flow and temperature distribution impact on flow maldistribution depending on the channel number of the plate heat exchanger were investigated by computational fluid dynamics (CFD) analysis to identify the maldistribution flow effects of the plate heat exchanger and suitable installation location of the measurement device. Channels located at the end of the header are confirmed to have excessive flow, while the flow rate of working fluid in channels near the inlet pipe is relatively low. The channel flow distribution degraded with an increase in Ntot,ch. In plate heat exchangers withNtot, ch = 20, 40, and 60, gamma(f,ch) was 18-21.3 %, 24.3-25.9 %, and 29.1-31.2 %, respectively, when (G) over bar (ch) = 100-500 kg/(m(2)center dot s). A jet flow occurs when the fluid flows from the channel to the outlet header; therefore, the velocity and temperature distribution inside the outlet header is not uniform. However, the mass flux and temperature distribution in the pipe become uniform owing to the swirl flow. Thus,(gamma vm)=93.5 %-95.3 % and MATD = 0.26-0.33 degrees C when (G) over bar (ch) = 100-500 kg/(m(2)center dot s) at DPL = 10, which indicates that the velocity and temperature distribution of fluids become uniform over that point.