A Modeling Approach for Simulating Heat Dissipation From Actuators and Electronic Components Embedded in Thermally Conducting Polymers

Thermally conductive polymer composites allow for creating multi-functional structures that offer both anchoring points for the embedded actuators as well as heat dissipation functions. This paper focuses on understanding the heat dissipation function through a coupled modeling of polymer melt flow to obtain fiber orientations along with orthotropic thermal conductivities is presented to simulate the dissipation of heat generated by an electrical component embedded in both unfilled and filled polymer structures. The performed simulations indicate that the gain in heat dissipation when using commercially available thermally conductive polymers results in 40% reduction in the operating temperature of the embedded electronic component. In the case of an embedded actuator, such as a pager motor, this is expected to significantly enhance performance. The orthotropic thermal conductivity resulting from fiber orientation was found to not significantly influence the heat dissipation function of the structural geometries that were studied in this paper. Therefore, in such cases the computational effort involved in modeling process-dependant orthotropic thermal conductivities can be omitted during the design of filled polymer structures with embedded actuators. Validation of the model was obtained through comparison of simulation predictions with experimental results for a simple embedded ceramic resistor and a more complex embedded motor in a model structure. We also found that increasing the thermal conductivity beyond the value of 2 W/m-K had very little impact on the heat dissipation function. This work establishes the feasibility of creating multi-functional structures from filled polymers by embedding actuators to facilitate the miniaturization of devices.