Development and Application of a Thin Flat Heat Pipe Design Optimization Tool for Small Satellite Systems

Abstract

With easier access to space and the increasing integration of power-dense components, small-scale thermal management solutions are in-demand for small satellite systems. Due to the strict mass and volume requirements commanded by such power-dense small spacecraft, heat pipes with thin and flat architectures provide a nearly ideal solution for the efficient transfer and dissipation of heat. Unlike traditional heat pipes, however, the performance of thin heat pipes is heavily dependent on detailed internal parameters, including the vapor core geometry and structural mechanics characteristics. In this study, the development and testing of a new computational modeling and optimization tool for the design of thin heat pipes is presented. The computational model is described in detail and includes parameters that define properties of the liquid wick, vapor core, and structural case. This model is coupled to a gradient-based optimization procedure that minimizes a multi-objective cost function expressed as a weighted sum of the total temperature drop, maximum heat dissipation, mass, and structural deflection for a range of operating conditions. The model is then used to optimize the design of a copper-methanol flat heat pipe applied to a small satellite mission. The flat heat pipe design is optimized with respect to both cold and hot orbital conditions.