Aavid created a CFD model of the existing device and fine-tuned the model parameters to match thermal testing data that was provided. The top aluminum spreader was modified to enhance radiative and convective heat transfer by increasing its effective surface area. Next the conductive heat transfer throughout the device was optimized to reduce temperature gradients between the hot spots and exterior surfaces. Strategically placed graphite sheets were added to spread the heat while insulating material was used to isolate heat from surfaces that will be in contact with the skin of the user.
To improve the aesthetics of the device, the aluminum spreader was mounted to the PCB suing bosses and numerous locations. The PCB itself was used as a part of the thermal system which enhanced performance. Additionally, the gap between aluminum spreader and critical devices on the PCB were filled using thermal interface material.
The baseline simulation results closely met the prototypes thermal test data. The top aluminum spreader was effective in removing heat from the systems. There was significant improvement to the aesthetics and usability by introducing other conductive and insulating materials such as pourable thermal interface material, graphite, foam, and the PCB itself.