Please wait a minute...
浙江大学学报(工学版)
J4  2013, Vol. 47 Issue (2): 249-255    DOI: 10.3785/j.issn.1008-973X.2013.02.009
    
Loss coefficient and rectification efficiency based on
valveless micropump
YING Ji, CAO Chao, JIAO Zhi-kai
Department of Mechanical Engineering,Zhejiang University,Hangzhou 310027,China
Download:   PDF(0KB) HTML
Export: BibTeX | EndNote (RIS)      

Abstract  

To get the proper total pressure/pressure loss theory of valveless micropump in the case of low reynolds laminar flow and make optimal design for each part of diffuser/nozzle component. Based on the principle of energy dissipation and pressure loss，the total pressure/pressure loss theory of valveless micropump was established. The finite element model of diffuser/nozzle component was built by using the finite element software and the flow simulation analysis was carried out. The effects of driven pressure, divergence angle on total pressure/pressure loss and rectification efficiency of diffuser/nozzle component was analyzed. The simulation results show that: the total pressure loss of each part of diffuser/nozzle component can not be ignored. When the dimensionless pressure pw greater then 6.4×104, the pressure loss of exit section can be regarded as 0. The total loss coefficient decrease with the increase of divergence angle and driven pressure. When pw less then 4.48×104 , the larger divergence angle micropump have better rectification efficiency, while pw great then 19.2×104, the smaller divergence angle micropump have better rectification efficiency.
Key words:

Published: 01 February 2013
CLC:  TH 38  
Service
E-mail this article
Add to my bookshelf
Add to citation manager
E-mail Alert
RSS
Articles by authors
Cite this article:

YING Ji, CAO Chao, JIAO Zhi-kai. Loss coefficient and rectification efficiency based on
valveless micropump. J4, 2013, 47(2): 249-255.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008-973X.2013.02.009     OR     http://www.zjujournals.com/eng/Y2013/V47/I2/249


无阀微泵损失系数及整流效率

为了得到适于无阀微泵所处低雷诺数层流条件下的总压/压强损失理论,对扩张/收缩管组件各部分进行优化设计.由能量耗散和压强降低原理,建立无阀微泵的总压以及压强损失理论;利用有限元软件,建立扩张/收缩管组件的有限元模型,进行流场仿真分析;分析驱动压强,扩张角对扩张/收缩管组件总压/压强损失以及整流效率的影响.仿真结果显示:扩张/收缩管组件各部分总压损失均不可忽略;当无量纲压力pw大于6.4×104时,出口段的压强损失可以认为是0;总损失系数随扩张角以及驱动压强的增大而减小;当pw小于4.48×104时,扩张角越大微泵整流效率越高;而当pw大于19.2×104时,扩张角越小微泵整流效率越高.

［1］ ANDERSSON H,WIGNGAART W,NILSSON P,et al. A valve-less diffuser micropump for microfluidic analytical systems ［J］. Sensors and Actuators B, 2001, 72（3）: 259-265.
［2］ ROSA S, PINHO F. Pressure drop coefficient of laminar Newtonian flow in axisymmetric diffuser ［J］.
International Journal of Heat and Fluid Flow, 2006, 27（2）: 319-328.
［3］ OLLSON A, STEMME E, STEMME G. Numerical and experimental studies of flat-walled diffuser elements for valve-less micropumps ［J］. Sensors and Actuators, 2000, 84（1/2）: 165-175.
［4］ WANG Yi-chun, HSU Jui-cheng, KUO Ping-chi, et al. Loss characteristic and flow rectification property of diffuser valves for micropump applications ［J］. International Journal of Heat and Mass Transfer , 2009, 52（1/2）: 328-336.
［5］ YANG Kai-shing, CHERT Ing-young, SHEW Bor-yuan, et a1. Investigation of the flow characteristics within a micronozzle/diffuser ［J］. Journal of Micromechanics and Microengineering, 2004, 14（1）: 26-31.
［6］ JING X-z, ZGOU Z-y, HUNG X-y, et al. Micronozle/diffuser flow and its application in micro valveless pumps ［J］. Sensors and Actuators A, 1998, 70（1/2）: 81-87.
［7］ 凌智勇,丁建宁,杨继昌,等.微流动的研究现状及影响因素［J］.江苏大学学报,2002,23（6）: 1-5.
LING Zhi-yong, DING Jian-ning, YANG Ji-chang et al. Research advance in microfluid and its influencing factors ［J］. Journal of Jiangsu University of Science and Technology, 2002, 23(6): 1-5.
［8］ PFAHLER J. Liquid transport in micro and submicro channels ［J］. Sensors and Actuators A, 1989, 22（1/3）: 431-434.
［9］ GREITZER E M, TAN C S, GRAF M B. Internal Flow: Concepts and Applications ［M］. New York: Cambridge University Press, 2004: 156.
［10］ 白兰,冯志庆,吴一辉. 基于MEMS的无阀泵的数值仿真与参数设计 ［J］. 微细加工技术, 2006, (5): 41-46.
BAI Lan, FENG Zhi-qing, WU Yi-hui. The numerical simulation and parametric design of valveless micropump based on the MEMS ［J］. Microfabrication Technology, 2006, (5): 42-46.
［11］ WHITE F M. Fluid mechanics ［M］.Beijing: Tsinghua University Press, 2005: 372,374,383.
［12］ NABAVI M, MONGEAU L. Numerical analysis of high frequency pulsating flow through a diffuser-nozzle element in valveless acoustic micropump ［J］. Microfluidics and Nanofluidics , 2009, 7(5): 669-681.
［13］ SCHLICHTING H, GERSTEN K. Boundary-layer theory ［M］. Bochum: Springer, 2000: 6,167.
［14］ OLLSON A, STEMME G, STEMMEe E. Diffuser-element design investigation for valveless pumps ［J］. Sensors and Actuators A , 1996, 57(2): 137-143.
[1] CAO Chao, YING Ji, JIAO Zhi-kai. Simulation of unsteady characteristics and rectification efficiency of valveless micropump[J]. J4, 2013, 47(6): 1036-1042.