Effect of baffles shape on the flow patterns and power consumption in stirred vessels

Abstract

Effects of the baffles shape on the fluid velocities, flow patterns and power consumption in vessels agitated by a six blade Rushton turbine are explored in this paper. The curvature of baffles, their length, position and width are the main parameters under investigation. The study is carried out by using the Computational Fluid Dynamics tool, for a range of Reynolds number in the turbulent flow regime from 104 to 105. The comparison between the straight and curved baffles revealed that the curved shape allows wider well stirred region and more powerful radial jet of fluid than the straight baffle. In addition, the increase in baffle curvature allows a reduction in power consumption. When partial baffles are inserted in the vessel, the lowest value of power number is obtained with baffles located at the upper part of vessel, followed by those located at the center and then at the lower part. Concerning the effect of baffle length, the baffles with partial length which are located at the center position in vessel require the lowest power consumption.