Experimental investigation into honeycomb heat sinks incorporating varying size slots for enhanced heat transfer

In this experimental investigation novel honeycomb heat sink designs that incorporate slots of varying length are presented. Thermal and hydrodynamic performance comparisons are made for a longitudinally-finned heat sink, a wavy wall heat sink of the same geometric dimensions, a closed channel honeycomb heat sink and a number of honeycomb heat sinks with different length (3mm, 6mm and 13mm) of vertically orientated slot. The heat sinks are manufactured using an investment casting process which provides a means of fabricating complex designs as one monolithic structure with high thermal conductivity that would not otherwise be possible using traditional techniques. It is demonstrated that enhanced heat transfer was achieved with the introduction of vertically oriented slots into the closed channel honeycomb structure. It is found that there is an optimum slot length per unit length of the heat sink and in the current experimental range the best performance was observed with 6mm length slots.