Mass transfer enhancement by pulsatile flows in grooved channels (the effects of groove length on the resonant mass transfer enhancement)

Abstract

The effect of groove length on the resonant mass transfer enhancement by pulsatile flow in grooved channel at intermediate Reynolds number was studied for five channels using experimental methods. The mass transport processes from the bottom of the groove to the channel were visualized by an electrolytic precipitation method, and overall and local mass transfer rates were measured by electrochemical methods with a high Schmidt number fluid. The qualitative and quantitative observations show that the range of Strouhal numbers, which gives inertia-dominated flow, is extended to the low-value region with groove length. Moreover, it is revealed that a noticeable enhancement is obtained in a specific channel at a Reynolds number for a wide range of Strouhal numbers. The results indicate that there is a specific Reynolds number for transfer enhancement in a channel.

An Experiment Investigation of Heat Transfer Enhancement by Pulsating Laminar Flow in Rectangular Grooved Channels

“…Jin [3] confirmed the existence of the optimum pulsation frequency for the maximum heat transfer enhancement. Nishimura [4,5] found that the optimal pulsation frequency depends on the opening size of rectangular groove and the Reynolds number. Kunitsugu [6] showed that for different groove sizes, the flow field structure within the groove showing large differences.…”

“…Nishimura [4,5] found that the optimal pulsation frequency depends on the opening size of rectangular groove and the Reynolds number. Kunitsugu [6] showed that for different groove sizes, the flow field structure within the groove showing large differences. He also indicated that there exists an optimal average Reynolds number corresponding to the maximum heat transfer enhancement factor depends on the groove size.…”