On the relation between the flow direction and the pressure drop in a channel with a serrated wall.

Abstract

The effect of flow direction on the pressure drop in a two-dimensional channel consisting of a periodically serrated wall and a plain one is studied numerically and experimentally under the steady state condition. The serrated wall is composed of lines inclined and lines perpendicular to the direction of the mean flow. The difference in the pressure drop due to the flow direction depends on the aspect ratio, the Reynolds number and the angle of inclination of the serrated wall. It is found that, in the range of the laminar flow, the pressure drop in the case that the fluid flows in the direction such that the cross-sectional area of the channel expands suddenly is large compared with that in the opposite case. This result is experimentally confirmed by using a water flow. The difference in the pressure drop due to the flow direction is found to take a maximum value in the comparatively small angle of inclination.