ABSTRACT
This chapter describes the convection process occurring in a class of air-cooled packaging configurations where conduction and radiation heat transfer are absent. It presents heat transfer correlations and calculation procedures that can be used to estimate package surface temperatures and coolant flow pressure drops. In addition, some packages may include heat sinks, and electrical cabling or card separators may partially obscure the flow. In order to develop a systematic description of convection in electronics, the chapter aims to restrict our attention to unobstructed flow over uniform arrays of equal-sized elements. Upon encountering a package array, the coolant is accelerated because of the reduced cross-sectional area available to the flow, and the shape of the velocity distribution changes. AZ Richard Wirtz et al. presents correlations for computing longitudinal fin heat sink performance in arrays of packages. Convection in uniform arrays containing low profile packages is strongly influenced by the bypass flow.
