The experimental study of the velocity field and power consumption has been conducted in a mixing vessel equipped with a two-bladed impeller for a viscoelastic fluid and Newtonian and non-Newtonian inelastic fluids for comparison. The results are interpreted in the light of a numerical simulation using a finite element method for an “Oldroyd B” fluid. Both numerically and experimentally a significant influence of elasticity is found for an effective Reynolds number greater than a threshold value Re* = 5 to 7. Above this value, the power number is increased and the velocity field deeply modified. This behavior is mainly related to elasticity of the fluid.
Issue Section:
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