Second law analysis of rectangular channels with square pin-fins

This paper presents heat transfer and friction characteristics, and the sec ond law analysis of the convective heat transfer through a rectangular chan nel with square cross-sectional pinfins attached over a flat surface. Vario us clearance ratios (C/H) and interfin distance ratios (S-x/D) were used, a nd optimum pin-fin arrays that minimize entropy generation were determined. It was found that (Nu) over bar number based on the projected area decreas ed with increasing S-x/D and C/H, whereas (Nu) over bar based on the total heat transfer area increased with increasing S-x/D and with decreasing C/H. The friction factor was found to decrease with increasing S-x/D and C/H. S maller entropy generation numbers were obtained at lower Reynolds number, h igher clearance ratio, and higher interfin spacing ratio. (C) 2001 Elsevier Science Ltd.