The combined effects of longitudinal heat conduction, flow nonuniformity and temperature nonuniformity in crossflow plate-fin heat exchangers

An analysis of a crossflow plate-fin compact heat exchanger, accounting for the combined effects of two-dimensional longitudinal heat conduction throu gh the exchanger wall and nonuniform inlet fluid flow and temperature distr ibution is carried out using a finite element method. A mathematical equati on is developed to generate different types of fluid flow/temperature maldi stribution models considering the possible deviations in fluid flow. Using these models, the exchanger effectiveness and its deterioration due to the combined effects of longitudinal heat conduction, flow nonuniformity and te mperature nonuniformity are calculated for various design and operating con ditions of the exchanger. It was found that the performance variations are quite significant in some typical applications. (C) 1999 Elsevier Science L td.