Effects of the channel width on heat-transfer augmentation in a sinusoidal wave channel

Abstract

This paper investigates how heat transfer and fluid flow are affected by the channel width as it is varied from small to large scale in a wavy sinusoidal channel. The mean Nusselt numbers in periodic fully developed regimes depend on the maximum Nusselt number at the reattachment point of the flow separated from the top of the peak, and reach maximum at P/H=2.0-1.6 (P: pitch, H: width); the friction factor becomes maximal at the same ratio P/H=2.0-1.6. The performance ratio ηII, at equal pumping power, attains a maximum at P/H=2.29-2.0. Thus, it can be concluded that the channel is optimal at P/H=2.0 for augmenting heat transfer.