Novel diffuser-nozzle micropump actuated by thermal bubble

A novel micro-machined valveless diffuser-nozzle micropump is presented in the present paper. The micropump is designed by thermally hubble driven actuation method. This pumping mechanism requires no mechanical moving parts for actuation and control of inlet and outlet. As a result, it requires substantially simplified fabrication process in two wafers, which is compatible with IC fabrication processes. The proposed micropump will provide high actuation stroke than existing micropumps. The micropump consists of a micro-heater, a micro-chamber, a diffuser and a nozzle. The fundamental operating principles of the thermally bubble driven diffuser-nozzle micropump are outlined with different dimensions of diffuser and nozzle. The detailed fabrication process flow to fabricate the micropump and qualitative pumping results are also described. A numerical method is developed to analyze and optimize the thermal processes involved in the operation of the micropump. A 2D moving boundary model has also been developed to simulate the bubble growth and fluid flow inside the micropump. Simulated result shows that the proposed micropump is capable to perform as an efficient diffuser-nozzle micropump. The potential areas of application of the proposed micropump are (i) lubrication of the nano/micro devices or engines, (ii) pumping of fuel into the nano/micro devices or engines, (iii) drugs delivery systems, etc.