Experimental study of mass transfer around a turbulence promoter by the limiting current method

Abstract Local mass transfer rates around a turbulence promoter in a channel having the geometry of zigzag-type or cavity-type characterized by the location of promoters have been measured by the limiting current technique. The experimental results showed that turbulence promoters are effective in breaking the concentration boundary layer and thus increasing the mass transfer rate. In the present experiment the Reynolds numbers were varied from 10 to 200 for the different aspect ratios of 3.5, 5 and 7. The experimentally obtained Sherwood numbers were compared with those numerically obtained by Kang and Chang. As a result, they were found to be in agreement to within an error of 20%.

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