3D CFD analysis of the effect of inlet air flow maldistribution on the fluid flow and heat transfer performances of plate-fin-and-tube laminar heat exchangers

Different computation test cases with a variety of inlet air flow distributions on in-line and staggered plate-fin-and-tube heat exchangers were run to systematically analyse their effects on system performance. The CFD results confirmed the importance of the influence of inlet fluid flow nonuniformity on heat exchanger efficiency. Results indicate that up to 50% improvement or deterioration in the Colburn j-factor are found compared to the baseline case of a heat exchanger with a uniform inlet air velocity profile. Moreover, the present investigation with respect to inlet flow maldistribution demonstrates that 3D CFD simulation is a useful tool for analysing, designing and optimising heat exchangers. Finally, the results of this study can be also of significant value for the optimum design of header and distributor configurations of heat exchangers to minimise maldistribution.