Additive manufacturing of pyramidal pin fins: Height and fin density effects under forced convection

This paper investigates the effects of varying the fin height and the fin density of pyramidal pin fins produced using cold spray technology. The thermal and hydrodynamic performance of this new type of fin array is evaluated using a forced convection heat transfer apparatus. The heat transfer efficiency of this type of extended surface is determined and correlations linking the Nusselt number, the Reynolds number, the fin height and the fin density are produced and validated. The geometric and thermo-hydraulic parameters affecting the thermal conductance of the pyramidal pin fin arrays are discussed. It is found that increasing either the fin height or the fin density also increases the total thermal conductance at the expense of a higher pressure loss.