Optimal design of a natural convection heat sink for small thermoelectric cooling modules

Metal additive manufacturing technologies are increasingly being adopted for rapid prototyping and to build geometrically complex designs for thermal management. This paper develops and experimentally validates a numerical model to design a high performance, small-scale heat sink for use with a thermoelectric cooling cap. The design was constrained by a heat load of 2.15 W, and a target average base temperature of 45 degrees C as a compromise between avoiding burn injury and reducing heat dissipation requirements. Over successive numerical iterations, an optimal natural convection heat sink was developed with an estimated thermal resistance of 10.9 K.W-1 and base temperature of 44.4 degrees C. This design featured an internal cavity in a tapered pin array, and was able to achieve a steady state base temperature that was 11.7 degrees C cooler than a conventional design, with 51% less surface area and significantly less material.