Valveless pumping systems are systems or devices which exploit system asymmetry and nonlinearity to drive flow without flow direction regulators Nowadays valveless micropumps are increasingly needed in micro-electro- mechanical systems (MEMS) and biomedical MEMS (BioMENS) Here we focus on the effects of wave propagation in a closed-loop valveless pumping system In particular a fluid-filled closed-loop system is considered which consists of a tank with a rigid tube connecting the two sides with an actuator producing waves that propagate in the tank A mathematic model is constructed and an analytic solution is derived by perturbation theory here There are two cases discussed in this thesis namely lab-size and real-life size system It shows that both of the two cases have the same trends such as no average flowrate produced when the actuator is located at a symmetry position Furthermore the amplitude and phase angle of the instantaneous flowrate are studied carefully to reveal their dependence on varies system parameters In addition a study of each of the dimensionless parameters in this system is carried out to demonstrate how the system response depends upon geometry frequency damping and inertia force Specially the amplitude of flowrate decrease with inertia parameter increase And increasing which is proportional to the reciprocal of damping will lead the amplitude of flowrate increase too We can conclude that combining the effects of some dimensionless parameters such as and frequency and the position of the actuator the maximum flowrate can be found from such results

An Analytical Investigation into Valveless Pumping Effects in a Closed-loop Water-wave System

欣潔, 何. (Author). 2014 8月 26

學生論文: Master's Thesis