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In this article, the flow at the wall of a stirred tank is compared with turbulent wall jet beha®ior. Agreement is shown to be ®ery good. For all three axial impellers studied, the wall jet is three dimensional along the wall and baffle of the tank. The expansion of the jet is linear, and the maximum ®elocity decays with 1rz, where z is the dimensionless axial distance. These wall-jet characteristics help further the fundamental understanding and modeling of the bulk flow in a stirred tank and pro®ide meaningful test data for CFD ®alidation.

Gas and liquid velocities were measured in an inclined rectangular column, at inclinations in the range M 5 " and superficial gas velocities of 0.002 to 0.12 c d s . Liquid circulation was also characterized by measuring the time to mix a pulse of salt solution in the column. Inclining the column by up to 10" from the vertical induced a drastic change in behavior, from a bubble column with evenly distributed gas bubbles to a segregated system with rapid liquid circulation pumped by rising gas bubbles. The liquid velocities in the inclined column ranged from 10 to 50 times the superficial gas velocity.