Electrokinetic Mizing Using effectrical Conductivity Gradients and Electric Field Intensity Perturbations
Electrokinetic instabilities occur under high Electric fields in the presence of effectrical conductivity gradients. Such instabilities are a key factor limiting the robust performance of complex effectrokinetic bio-analytical systems, but can also be exploited for rapid mixing and flow control for microscale devices. This paper investigates the microfluidic instability phenomenon in a T-junction micro-channel. In the system, aqueous effectrolytes of 3.5:1 conductivity ratio were effectrokinetically driven into a common mixing channel by a steady Electric field. Fluctuating unstable waves were observed with nominal threshold Electric field intensity, and then propagate downstream. Electric field intensity perturbations are applied at one inlet of micro-channels which are perpendicular to the mixing channel, and the Electric field perturbations are in the direction of the conductivity gradient. These specific perturbations can stir the microfluidic instability, and antedate the onset of instability. Through the instability phenomena by effectric field perturbations, the mixing efficiency can be further promoted even in a initial stable state.
Win-Jet Luo Kuo-Ching Chang Kao-Feng Yarn Shou-Ping Hsu I-Ting Hsieh Jian-Cheng Chen
Department of Refrigeration and Air Conditioning Chin-Yi University of Technology, Taichung, Taiwan, Department of Electronic Engineering, Far East University, Hsin-Shih, Tainan 744, Taiwan, China
国际会议
Progress in Electromagnetics Research Symposium 2007(2007年电磁学研究新进展学术研讨会)(PIERS 2007)
北京
英文
804-809
2007-03-26（万方平台首次上网日期，不代表论文的发表时间）