A Study of Dispersed Phenomena on Rushton and Rushton V-CUT

Varit Kunopagarnwong, Thongchai Rohitatisha Srinophakun, Wisarut Manasthammakul

Abstract


The flow behavior of liquid-solid particles in mixing tanks using a modified Rushton impeller, called a Rushton V-cut impeller, was studied. Both the Rushton and Rushton V-cut impellers were compared at a 300 rpm stirring speed and a 10 % wt solid concentration. Hydrodynamic behaviors, such as solid volume fraction, velocity, pressure, and shear stress, in both the Rushton and Rushton V-cut impellers were investigated. Computational fluid dynamics (CFD) software able to understanding of hydrodynamics of stirring liquids which contain solid particles. CFD programme was to predict the mixing flow of the highly viscous system. Therefore, the present work was carried out using CFD software with the Eulerian-Eulerian approach with a turbulent k-ε model. The simulation of mixing tanks was consisted of moving and stationary zones by using moving references frame method or MFR. The results were observed that Rushton V-cut can dramatically reduce pressure up to 20% and the shear stress up to 64.38% while keeping the liquid-solid mixing at a considerable degree. Therefore, this design can reduce the power consumption.

Keywords


Computational fluid dynamics (CFD); Rushton impeller; Flow behavior

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DOI: https://doi.org/10.24203/ajas.v6i4.5428

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