This work was also presented at IChemE's "John Smith's Day" at the University of Birmingham in January, 2000, under the title "A New Gas Dispersion Impeller with Vertically Asymmetric Blades" (PDF file; 1.2Mb).
Here we see the velocity magnitudes in a horizontal plane through the impeller. The highest velocities are found near the tip of the impeller blades. The impeller creates a radial jet. It is rotating clockwise, with the concave ("open") face forward.
The impeller, shaft, baffles, bottom, and liquid surface are colored by liquid velocity magnitude. Red and blue denote high and low velocities respectively. The highest velocities are found on the impeller blades. The simulations predicted a power number of 2.2, which is within 5% of the measured power number.
The simulations were performed using a multiple reference frame (MRF) model. A fully unstructured tetrahedral mesh was used, with approximately 400k nodes. The mesh was relatively fine near the impeller blades and coarser far away from the impeller.
This image shows the grid on the tank walls.
View Next Page
Return to Table of Contents
Last Updated December 16, 1998 by André Bakker © André Bakker 1998