電熱力微混合器的研究

Study of Electro-Thermal Micro Mixer

黃俊傑(Jun-Jie Huang)

指導教授 ： 李雨

國立臺灣大學/工學院/應用力學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.01921

摘要

本論文所研究的電熱力微混合器就是一個主流道底壁上建置有適當電極陣列的對稱Y型微流道，電熱力會在電極角落上方產生渦旋對，攪拌流體，以促進混合。本研究利用微機電製程技術，製作出多種電極角度(長條型電極與主流道的夾角)、電極數目與排列幾何的陣列，來進行測試。首先利用參有微粒子的電解質流體，在顯微鏡下直接在流道內觀察電極通電後電解質流體所產生的電熱力渦流，探討其特性，以設計能促進混合效果的電極陣列。共探討斜電極、鋸齒狀電極及階梯式電極三種陣列，其中階梯式陣列可在主流道兩側壁間佈滿電熱力渦流，創造出可將左(或右)半側流體以接力式的方式捲入右(或左)半側流體內的流場，故本研究採用六對一組的階梯式陣列(其電極角度有30

關鍵字

電熱力 ； 渦旋 ； 微流混合器

並列摘要

The electro-thermal mixer in the present thesis is a Y-type micro channel with designed electrode array(s) built on the bottom wall of the main channel. Vortex pairs are generated above the corners of electrodes due to the electro-thermal force. The vortices stir the fluid and enhance mixing. Various electrode arrays with different electrode angles (angle between the strip electrode and the main channel), different numbers and different geometries are fabricated via MEMS techniques. We first study the characteristics and the mixing behavior of vortices via the motion of micro particles suspended in the fluid inside the channel. Three arrays were designed, including the inclined type, the saw-tooth type and the staircase type, and all of them can induce cross stream-wise flow for mixing enhancement. The vortices generated by the staircase type array spread over the channel, which can transport fluid across the channel in a more effective way, and was chosen for the mixer design. Three groups of array with six pairs of electrodes in each group (may have different electrode angles, 30

並列關鍵字

Electro-thermal force ； vortices ； micro-mixer

參考文獻

(14) 劉振邦, “粒子操控之微混合器晶片開發”, Master thesis, Institute of Applied Mechanics, National Taiwan University, (2005).

(1) Becker F. F., X. B. Wang, Y. Huang, R. Pethig, J. Vykoukal and P. R. C. Gascoyne, “The removal of human leukaemia cells from blood using interdigitated microelectrodes”, Journal of Physics D: Applied Physics, Vol.27, 2659-2662, (1994).

(2) Gonzalez A., A Ramos, H. Morgan, N. G. Green and A. Castellanos, “Electrothernal flows generated by alternating and rotating electric fields in microsystems”, J. Fluid Mech., Vol. 564, 415-433, (2006).

(3) Hiroaki Suzuki, and Chih-Ming Ho, "A Chaotic Mixer for Magnetic Bead-Based Micro Cell Sorter", J. Microelectromech. Syst., Vol.13, 779-790, (2004).

(4) Liu R. H., M. A. Stremler, K. V. Sharp, M. G. Olsen, J. G. Santiago, R. J. Adrian, H. Aref, and D. J. Beebe, "Passive mixing in a three-dimensional serpentine microchannel", J. Microelectromech. Syst. Vol. 9, 190–197, (2000).