TY - GEN
T1 - Unsteady in-plane vortex motion in a microchannel liquid flow
AU - Lee, Lap Man
AU - Hau, Winky Lap Wing
AU - Lee, Yi Kuen
AU - Wong, Man
AU - Zohar, Yitshak
PY - 2005
Y1 - 2005
N2 - An unsteady flow can dramatically enhance the mixing efficiency in a highly localized region, as the flow would become chaotic if time is an independent variable. In this work, the response of uniform electroosmotic flow to an oscillating electric field is first examined experimentally and numerically as a function of the driving frequency. Then a steady in-plane micro vortex flow pattern, traced by microparticles, is realized and compared to numerical simulations. Upon confirmation of the simulations for uniform but unsteady and steady but non-uniform flows, the CFD code has finally been applied to study unsteady non-uniform flow field, for which it is difficult to measure flow properties. The time evolution of liquid vortex motion in a microchannel, due to either sinusoidal or sudden electric field reversal, is numerically investigated revealing the relationship between length and time scales dominating momentum transfer in electrokinetically-driven unsteady liquid flow.
AB - An unsteady flow can dramatically enhance the mixing efficiency in a highly localized region, as the flow would become chaotic if time is an independent variable. In this work, the response of uniform electroosmotic flow to an oscillating electric field is first examined experimentally and numerically as a function of the driving frequency. Then a steady in-plane micro vortex flow pattern, traced by microparticles, is realized and compared to numerical simulations. Upon confirmation of the simulations for uniform but unsteady and steady but non-uniform flows, the CFD code has finally been applied to study unsteady non-uniform flow field, for which it is difficult to measure flow properties. The time evolution of liquid vortex motion in a microchannel, due to either sinusoidal or sudden electric field reversal, is numerically investigated revealing the relationship between length and time scales dominating momentum transfer in electrokinetically-driven unsteady liquid flow.
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U2 - 10.1109/MEMSYS.2005.1454034
DO - 10.1109/MEMSYS.2005.1454034
M3 - Conference contribution
AN - SCOPUS:26844459938
SN - 0780387325
T3 - Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)
SP - 734
EP - 737
BT - Proceedings of the 18th IEEE International Conference on Micro Electro Mechanical Systems, MEMS 2005 Miami - Technical Digest
T2 - 18th IEEE International Conference on Micro Electro Mechanical Systems, MEMS 2005 Miami
Y2 - 30 January 2005 through 3 February 2005
ER -