Thermal Design of the Selected Compact Heat Exchanger

Abstract

Interest in a heat exchanger in compact form—and its surfaces with a high ratio of heat transfer area to core volume—is rising at an accelerated pace. The main reasons for the use of such compact surfaces are that smaller, lighter-weight, and lower-cost heat exchangers result. Such approach gains us both the direct geometric advantages of higher area density as well as higher heat transfer coefficient for the smaller flow passage in particular under laminar regime and conditions. Due to the smaller flow passage hydraulic radius, with gas flows particularly, the heat exchanger design range for the Reynolds number usually falls well within that laminar flow regime. Then it follows that theoretically derived laminar flow solutions for fluid friction and heat transfer in ducts of various flow cross-section geometries become important. Toward the end of this chapter two types of compact heat exchangers are selected, namely Printed-Circuit Heat Exchanger (PCHE) and Plate-Fin Heat Exchanger (PFHE), and 1-D and 3-D analysis are presented for their design for a Solar Gas Turbine Power plant based on work done by Yakah [1]; and we have used and presented all the works done in this reference.