Effect of Geometry Design on Mixing Performance of Newtonian Fluids using Helical Overlapped Mixer Elements in Kenics Static Mixer

Authors

1 Department of Mechanical Engineering, University of Sciences and Technology USTO-MB, PB 1505 El Mnaouer ‎31000 Oran, Algeria‎

2 Laboratory of Energy of Dry-Zones (ENERGARID), Faculty of Sciences and Technology, University of Bechar, BP 417 Bechar, Algeria

3 Aeronautics Laboratory and Propulsion Systems, USTO-MB,PB 1505 El Mnaouer 31000 Oran, Algeria

Abstract

The laminar flow pattern and mixing behavior of incompressible Newtonian fluids in different modified mixer ‎configurations were numerically investigated using Computational Fluid Dynamics (CFD) simulations in the range of ‎Re=0.15-100. The governing equations were solved by ANSYS Fluent 14 using the second-order finite volume method ‎‎(FVM) and the SIMPLE algorithm scheme. The computational model is assessed by comparing the predicted pressure ‎drop results to empirical correlations in the literature. The effects of incorporated helical overlapped mixer elements and ‎the diameter aspect ratio (C) on the mixing efficiency for different mixer geometries were examined and evaluated by ‎characteristics measures of Intensity of Segregation (IOS), pressure drop, extensional efficiency, and G-factor. The ‎performance of new modified mixers is evaluated via comparison with the standard industrial Kenics static mixer. The ‎static mixers with modified internal geometry achieved fast mixing and better mixing quality than the Kenics mixer. ‎Besides, an increase in diameter aspect ratio C benefited from a decrease in pressure drop within the static. The ‎modified mixer: C=1.5 was found to have the highest mixing efficiency, concerning short mixing length with marginally ‎higher pressure drop than the other mixers. In contrast, the mixer: C=2 is the most efficient based on low pressure drop ‎and energy requirement with slightly greater mixing length‎‎.

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