The Adiabatic Heat Transfer Coefficient and the Superposition Kernel Function: Part 2—Modeling Flatpack Data as a Function of Channel Turbulence

Abstract

This paper describes an investigation of the forced convection heat transfer and pressure drop characteristics of a regular in-line array of flatpacks for several channel heights and inlet velocities. The work has both practical and theoretical interest since it relates to technical problems now faced by the electronics industry, and it embodies one of the most general heat transfer problems: nonuniform heat release from nonuniform geometries. To predict operating temperatures in situations where the wall temperature distribution is nonuniform, one must use superposition. Both the adiabatic heat transfer coefficient, h ad and the superposition kernel functions, g * are required. The problem can be solved using superposition directly (h ad and g *) or indirectly (using h ad and g * to calculate the correct value of h m ). Either way the superposition data is required. This work presents the first full set of superposition data for flatpack arrays. Part 1 presents heat transfer and pressure drop results and part 2 presents a model for heat transfer that is based on the maximum turbulence fluctuations in the channel.