Energetic Correlation of Local Mass Transfer in Swirling Pipe Flow

Abstract

Mass transfer measurements in a decaying swirl flow in a pipe were carried out, using the electrochemical limiting diffusion current technique. The measurements were taken from local electrodes of 1 mm diameter without a developing concentration boundary layer around. Swirl was generated using short helical guide-vanes with vane angles between 15 and 60° at the outer edge of the vanes to the duct axis. The pressure drop measurements were also taken to perform an energy analysis. For a Reynolds number range of 1700−10000, the overall energy correlation for a representative length of 36.5 diameter were evaluated to be Shs(Sc)-0.33 = 0.3705(1 + tan θo)-0.120 X0.236, where θo is the vane angle at the outer edge of the helical swirler and X is the energy dissipation parameter.