Ultrasonic Traveling Wave Microfluidic Driver And Control Technology Research

With the developing of microflow systems, microflow driving & controlling technique has become one of the key techniques starved for solution. In this paper, a new technique- ultrasonic traveling wave microflow driving & controlling technique is presented. Using the anti-piezoelectric effect of piezoelectric ceramics, ultrasonic traveling wave on the pipe wall is generated, which performs elliptic motions of the pipe wall's surface points. Then sound field is generated and the liquid in the pipe flows along with the direction of traveling wave because of the effects of Renault shearing stress, viscous stresses and molecule force. Compared with the traditional methods, this technique has many advantages, such as no movable components, simple control method and higher control precision.This dissertation is supported by Nation Nature Science Foundation of china (No.10572078) and Shandong Province Excellent Youth Scientist Foundation (No.2004BS05006). For the feasibility and driving model of ultrasonic traveling wave microflow driving & controlling technique of the items, this paper has an embedded research from the view of dynamics analysis.Firstly, this paper introduces the status of microflow driving technique inside and outside the country, analyses particularly the mechanism of traveling wave's generating and elliptic motions, presents embeddedly the anti-piezoelectric effect,the character of material and frequency of piezoelectric ceramics, which makes a base for the driving & control of traveling wave microflow, and analyses the generating condition of acoustic streaming, then based on all the analysis, the feasibility of traveling wave's driving & controlling technique is validated primarily by experiments. Secondly, using ANSYS finite element software, this paper analyses respectively the modal of cirque and straight pipe shape: by the mode analysis, we get the modal's inherent frequency and vibration modal, and by researching the structure parameters' influence on vibration modal and frequency, the relation between cirque's inner diameter,elastomer ply and vibration mode,frequency is educed; this relation offers gist for the arrangement and connection of piezoelectric ceramics. Thirdly, by analyzing the harmonic analysis, the...