Chapter I - Introduction

Abstract

This chapter presents the introduction to laminar flow heat transfer. Interest in heat exchanger surfaces with a high ratio of heat transfer area to core volume is increasing at an accelerated pace. The primary reasons for the use of these more compact surfaces are that smaller, lighter-weight, and lower-cost heat exchangers are the result. These gains are brought about both by the direct geometric advantage of higher area density and also a higher heat transfer coefficient for the smaller flow passages. Because of the smaller flow passage hydraulic radius, with gas flows particularly, the heat exchanger design range for the Reynolds number usually falls well within the laminar flow regime. Thereafter, theoretically derived laminar flow solutions for fluid friction and heat transfer in ducts of various flow cross-section geometries become important.