Thermal Spreading Resistances in Rectangular Flux Channels: Part I Geometric Equivalences

Abstract

This paper presents a simple geometric tramsformation for predicting thermal spreading resistance in isotropic and compound rectangular flux channels using the solution for an isotropic or compound circular flux tube. It is shown that the results are valid for a wide range of channel aspect ratios and source to base coverage ratio. Since the circular disk solution requires a single series summation, it is preferable to the rectangular flux channel solution which requires the evaluation of two single series and one double series summation.