G0500405 Whole-field flow measurement inside a stirred mixer using Tomographic PIV technique

Abstract

We carried out phase-locked Tomographic PIV measurements in a square shaped, vertically-oriented water tank, in order to understand its general flow behavior and turbulence shear stress distributions in detail. The three-dimensional experiments are carried out at four different, 40 mm thick, vertical volume sheets. The water is stirred by a commercially available impeller, which has three symmetrical twisted blades. The impeller is rotated at the constant angular speed of 150 RPM. The Reynolds number of the flow, based on the blade's tip velocity and the impeller diameter, is 59400. In the present study, we carry out the flow measurements at two angular locations, so that the combined flow field would enable us to fully understand how the tip-generated vortices bend and diffuse in the flow domain. Exploring behavior of the tip-generated vortices are of prime interest to us, because the turbulence kinetic energy happens to be primarily concentrated inside these vortices.