Microsystem Technologies

, Volume 14, Issue 9–11, pp 1317–1323 | Cite as

Effect of baffle height and Reynolds number on fluid mixing

  • C. K. ChungEmail author
  • C.-Y. Wu
  • T. R. Shih
Technical Paper


In this paper, both numerical simulation and experiment were performed to investigate the mixing process within mixing chambers of the planar micromixer with three baffles at varied baffle height. The presence of three baffles causes the flow to separate and creates the recirculation and back flow within mixing chambers. The fluid mixing was greatly influenced by the baffle height and Reynolds number (Re) related to the size of recirculation zone. Larger baffle height or Re produces larger recirculation zone and convective mixing. The micromixer with 350 μm high baffles in 400 μm wide channel results in over 95% mixing at Re = 80 from the simulation results. The experiment results confirm the above simulation results qualitatively. This planar micromixer has the merits of simple design and easy fabrication as compared to the three-dimensional passive micromixers.


PDMS Pressure Loss Master Mold Image Capture System Passive Micromixers 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work is partial sponsored by National Science Council (NSC) under contract No NSC 94-2212-E-006-055. We pay our great thanks to the Center for Micro/Nano Science and Technology (CMNST) in National Cheng Kung University for the access of process and analysis equipments. We would also like to thank National Center for High-performing Computing (NCHC) for providing a computational fluid dynamics software in this work.


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.Department of Mechanical Engineering, Center for Micro/Nano Science and TechnologyNational Cheng Kung UniversityTainanTaiwan, ROC

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