NDLI: Numerical Modeling and Experimental Investigation of Improved Mixing From Both Coriolis Effect and Go¨rtler Vortices in Rotating Zigzag Microchannel

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Numerical Modeling and Experimental Investigation of Improved Mixing From Both Coriolis Effect and Go¨rtler Vortices in Rotating Zigzag Microchannel

Content Provider	The American Society of Mechanical Engineers (ASME) Digital Collection
Author	Ren, Yong Leung, Wallace Woon-Fong
Copyright Year	2011
Abstract	The flow pattern and mixing performance in different geometries of microchannels are investigated. A study for the zigzag shape channel under both stationary and rotation condition was investigated. The results are compared to the straight channel. Both numerical model via CFD and experiments are agreeing with each other. It is found when the channel is under rotation, the mixing performance is better than the stationary condition due to rotation induced Coriolis effect. As the rotation speed increases from 300rpm to 900rpm, an improved mixing performance can be further obtained. Our study results also demonstrate that zigzag channel can provide relatively better mixing, because the successive bending design can lead to secondary flow in the cross sectional directions due to Go¨rtler vortices generated from centrifugal effect as the flow negotiates the “turns” or “bends” of the channel, and this adds to mixing in addition to that due to aforementioned Coriolis effect. An analysis reveals that zigzag shape channel requires more pressure drop when compared with the straight channel in order to maintain the continuous throughflow due to the pressure/head loss as the flow encounters each bend and these losses become additive. This adds to the cost for the improved mixing from the Go¨rtler vortices.
Starting Page	1131
Ending Page	1134
Page Count	4
File Format	PDF
ISBN	9780791854921
DOI	10.1115/IMECE2011-64712
Volume Number	Volume 6: Fluids and Thermal Systems; Advances for Process Industries, Parts A and B
Conference Proceedings	ASME 2011 International Mechanical Engineering Congress and Exposition
Language	English
Publisher Date	2011-11-11
Publisher Place	Denver, Colorado, USA
Access Restriction	Subscribed
Subject Keyword	Design Computer simulation Computational fluid dynamics Coriolis force Pressure drop Vortices Shapes Flow (dynamics) Rotation Pressure Microchannels
Content Type	Text
Resource Type	Article

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