MEMS/NEMS
The Hong Kong University of Science and Technology

Professor Yi-Kuen Lee's MEMS/NEMS Group

Project --- The Latest Projects from the lab

Design, Fabrication and Characterization of Micro Chaotic Mixer

Micromixers are one of the key components in biochip or micro Total Analysis System. Since turbulence is difficult to generate for mixing in micro scale, there are many different kinds of micromixers fabricated by MEMS technology in recent years.

An active micromixer has been successfully demonstrated with periodic pneumatic forcing using Deep RIE etching and anodic bonding technology. A series of micromixer design programs based on kinematic as well as full CFD models have been developed to facilitate the design of micromixers for use with different biofluids in bioanalytical microsystems. In addition, the fundamental mixing mechanism of micromixers has been explained by using nonlinear dynamic system and continuum fluid mechanics principles.

Currently, the micro mixer research will be applied to the design of microfluidics-based biosensor for environmental monitoring.


Optical micrograph of silicon micromixer. Main channel size is 100


Single cross micromixer


Poincar section as a function of perturbation

Reference:

X. Niu, Y.K. Lee, "Efficient Spatial-temporal Chaotic Mixing in Microchannels", Journal of Micromechanics and Microengineering, Vol. 13, No. 3, pp.454-462, 2003.

X. Niu, Y.K. Lee, "Finite Time Lyapunov Exponent for Micro Chaotic Mixer Design" , ASME IMECE 2003, Washington DC, Nov 16-21, 2003.

Y.-K. Lee, "Lyapunov Exponents of a Micro Chaotic Mixer," International Journal of Nonlinear Sciences and Numerical Simulation,  Vol. 3, No.3-4, pp.561-563, 2002.

Y.-K. Lee, J. Deval, C.M. Ho, P. Tabeling, "Chaotic Mixing in Electrokinetically and Pressure Driven Micro Flows," IMRET 5: Proceedings of the 5th International Conference on Microreaction Technology, Strasbourg, France, pp.185-191, 2001.

Y.-K. Lee, J. Deval, P. Tabeling, and C.M. Ho, "Chaotic Mixing in Electrokinetically Pressure Driven System Flows," ; IEEE 14th International Conference on  Micro Electro Mechanical System (MEMS 2001), Interlaken, Switzerland, pp.483-486, 2001.

Y.-K.Lee, P.Tabeling, C. Shih and C.M. Ho, "Characterization of a MEMS-Fabricated Mixing Device," Proceeding of MEMS, ASME International Mechanical Engineering Congress and Exposition, Orlando, Florida, Nov, pp.505-511, 2000.

Background

Introduction to Continuum Mechanics, W.M. Lai, et al., Elsevier, 1993.

The Kinematics of Mixing: Stretching, Chaos, and Transport, J.M. Ottino, Cambridge University Press, 1989.

Regular and Stochastic Motion, A.J. Lichtenberg and M.A. Lieberman, Springer-Verlagn, 1983.

Nonlinear Oscillations, Dynamical Systems and Bifurcation of Vector Fields, J. Guckenheimer and P. Holmes, Springer-Verlag, 1983.

Global Bifurcations and Chaos - Analytical Methods, S. Wiggins, Springer-Verlag, 1988.

Mathematical Methods of Classical Mechanics, V.I. Arnold, Springer-Verlag, 1980.

Classical Dynamics : a Contemporary Approach, J.V. Jose and E.J. Saletan, Cambridge Univ. Press, 1998.

H. Aref, The Development of Chaotic Advection, Physics of Fluid, 14(4), 1315-1325, 2002.



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Prof. Yi-Kuen Lee's MEMS/NEMS Group
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