Performance evaluation of near-net pyramidal shaped fin arrays manufactured by cold spray

Near-net pyramidal shaped fin arrays have been produced using the Cold Gas Dynamic Spraying (CGDS) process. Some fin arrays have been modified to trapezoid prism geometry by grinding the top of the pyramidal fins to study the effect of varying the base angle, at a constant fin height. All fin arrays have been tested for thermal and hydrodynamic performance. Little variation in thermal conductance between ground and as-sprayed fins is observed for the same fin heights, while a slightly more significant variation in pressure loss through the fin array is found. A comparison of these performances was performed with plain rectangular fins. The new fin geometry outperforms the traditional rectangular fins when comparing the thermal conductance per unit pumping power for a given heat exchanger volume over the range of Reynolds numbers studied.