Experimental and numerical investigation of flat plate fins and inline strip fins heat sinks

Abstract

The flow and heat transfer characteristics of two analogous heat sinks were obtained from laboratory experiments and compared to each other and to numerical simulations. One contained continuousstraight fins, and the other inline strip fins, both cooled by forced airflow parallel to their base. The averageairflow velocity in the interfin channels ranged from 4 to 20 m/s, corresponding to Reynolds numbers from810 to 3,800. The measurements indicated that despite its smaller heat exchange area, the strip fins heat sinkconvective coefficient was larger enough to obtain a thermal resistance smaller than that of the continuousfins. Numerical simulations were performed to compare their results with the experiments. Two distinct fintreatments were used: one considered fins with no thickness, isothermal with the fins base temperature. The other considered the fins thickness and perfect thermal contact with the heat sink base. The Nusselt number simulation results for the continuous fins agreed within 3% with the measurements, but larger deviations were observed for the strip fins heat sink.