Experimental researches on the convective heat transfer in a channel packed with disordered particles

Channels packed with disordered particles are of great importantance for enhancing heat transfer. This paper builds the convective heat transfer experiment platform and studies the heat transfer coefficient in a channel packed with disordered cement particles experimentally. Under the given heat sources, cooling the channel with air at steady state obtains the data, which calculates the convective heat transfer coefficient. Then fitting the Nusselt and Reynolds numbers offers the experimental correlation. Error analysis and comparison with the existing correlations validate the fitted correlation. Discussion on the Nusselt number and wall temperature shows that the Nusselt number in the packed channel is approximately eight times than that in the smooth channel, which provides an effective method for intensifying the effect of channel wall cooling. Moreover, the inner wall temperature of channel with smaller particles is lower, which means the heat transfer enhancement performs better. (C) 2019 The Authors. Published by Elsevier Ltd.