The combined effects of AR and channel-taper or divider wall-to-tip distance by adjusting the incli- nation/length of the divider wall on the thermal performances of the two-pass channels were comparatively examined [10,11]. The most salient AR impacts on the distributions of Sherwood number (Sh) emerge over the flow regions where the maximum and mini- mum mass/heat transfer rates were developed [10]. In general, the averaged endwall HTE ratios decreased against AR for any smooth- walled tapered channel; while the improved heat transfer perfor- mances were concluded for the channels with relatively low AR and a divider wall that was parallel or slightly inclined toward the converging outlet-leg sidewall [10]. Regarding the effect of dis- tance between divider-tip and top-endwall of a 180 sharp bend, the smaller tip-to-wall distances increased the heat transfer rates on top endwall and outlet channel but at the cost of increased pres- sure losses [11].