论文信息 - THE EFFECT OF RHEOLOGICAL COMPLEXITIES ON POWER CONSUMPTION IN AN AERATED, AGITATED VESSEL

THE EFFECT OF RHEOLOGICAL COMPLEXITIES ON POWER CONSUMPTION IN AN AERATED, AGITATED VESSEL

Abstract Power for agitation has been measured under aerated and unaerated conditions in a 0.29 m vessel of Rushton dimensions at specific powers up to 18 W/kg. The fluids studied were water. Newtonian solutions up to 19 m Pas and non-Newtonian shear thinning fluids some of which also exhibited a yield stress and some of which were viscoelastic. For the unaerated case, the power number-Reynolds number plot is in good agreement with the literature. For the aerated case, the result can conveniently be divided into three Reynolds number regions. At Re > ∼900, the data obtained for the solutions is not markedly different to that for water except that a higher impeller speed is required to achieve complete gas dispersion. For ∼ 10 < Re < ∼900. the power drawn is independent of gassing rate and greater levels of elasticity and the presence of a yield stress leads to the lowest power numbers. For Re < ∼10, the gassed and ungassed power numbers are equal.

A. W. Nienow | J. Vlcek | V. Machon | D. J. Wisdom | J. Solomon

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