Optimization of high heat flux thermal energy storage with phase change materials

Future military systems such as high energy lasers and high power microwaves will require the development of high flux thermal energy storage (TES) systems to reduce the mass and volume of the thermal management system. Phase change materials (PCMs) should have a large latent heat of fusion. The PCM is usually impregnated into a solid matrix of high thermal diffusivity so that unacceptably large temperature increase at the heat source can be avoided. In this paper, a model was established for a TES medium with PCM filled channels. Two coupled one-dimensional transient heat conduction equations were solved to simulate the conjugated heat transfer in the wall and solid/liquid phase change in the PCM. A parametric study was conducted to investigate the effects of the channel configuration on the TES performance. An optimization study was carried out to minimize the temperature spike at the heating surface while maximizing the rate of heat absorption and specific storage capacity. The result of this study can also be used to provide an optimal design for a wax-filled carbon foam structure.