Two-pass countercrossflow heat exchangers with both fluids unmixed throughout

Abstract

The aim of this paper is to present the formulas for computing the effectiveness and spatial temperature distribution of each stream and the wall of the two-pass countercrossflow heat exchangers with both fluids unmixed throughout for all possible flow arrangements. Making the usual idealizations for analysis of any heat exchanger flow arrangement and giving the coupling conditions for each pass, the problem of finding the spatial temperature distributions in the crossflow heat exchanger core is reduced to the solution of Fredholm's second order integral equation. By using the collocation method the solution of this integral equation is obtainable in the form of power series. The explicit formulas for the spatial temperature distributions and effectiveness are then obtained by simple integrations. The new relations are particularly helpful for computer-aided design procedures of two-pass countercrossflow heat exchangers. © 1986 Springer-Verlag.