DESIGNED PERIODIC CELLULAR MATERIALS FOR ENHANCED AIR-COOLED HEAT SINKS
Stochastic metal foams available commercially enable multifunctional applications. However, stochastic metal foams with cells of random shape, morphology and distribution, often place materials in locations where their contribution to overall material properties is near negligible. The major drawback is the lack of control of open-cell mesostructures. On the other hand, periodic cellular structures lend themselves well to topology optimization & integration of multiple functions enabling superior performance benefits. We present a 'designed' periodic structured heat sink approach for enhancement of air-cooling of a heated substrate. Open-cellular periodic structures in a corrugated arrangement (similar to pleated filters or wall-flow filters) are mounted on the substrate as fin materials for high-performing heat sinks for applications in electronics cooling as they are likely outperform existing heat sink designs. Corrugated structures for these porous foam fins offer high effective surface area and lend themselves well to heat transfer density maximization subject to topological constraint (constraint that ensures highly uniform flow distribution of incoming flow across
the serpentine geometry). To design periodic structures, a two-pronged approach is undertaken. The analytical investigation deals with an approximate yet reliable model for the flow distribution in the corrugated system as well as a means of theoretically approximating optimal geometrical topology (porosity) that leads to maximal heat transfer density
at the microscopic level. The computational prong of the investigation helps corroborate results from the analytical model and in paving the path to making suitable choices for the optimal geometry. The parametric study through numerical computations and the analytical model together help integrate the macroscopic and microscopic schemes of heat transfer optimisation.