A Pumping-Mixing Microfluidic Device with a Microrotor

• Main Authors: Yu-Chih Hung, 洪御誌
• Other Authors: Horn-Jiunn Sheen
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/88625960157850680374

碩士 === 國立臺灣大學 === 應用力學研究所 === 96 === For microfluidic flows, one of the very important subjects is to have two or more fluids thoroughly mix in a short time and distance. In this study, a new microfluidic device possesses both pumping and mixing capabilities has been successfully developed by MEMS techniques. The flow was driven by a PZT valveless micropump and a microrotor was integrated into the pumping system. The oscillatory flow provided by the pumping chamber impinged the microrotor blades to have the microrotor rotate. The dimensions of the present micro-device are 25 mm in length, 11 mm in width, and 0.65 mm in thickness. The results revealed that mixing qualities were affected by rotating speeds of the microrotor, which depended on the driving frequencies and voltages. The mixing efficiencies were significantly enhanced by increasing the rotating speed which could rapidly stir the two different fluids and increase their interfacial areas. In this experiment, the flow rates of 15-130ul/min were measured at excitation voltages of 10-40 Vpp and frequency of 0.1k~1.5 kHz. Moreover, results show that good mixing efficiencies were demonstrated and the mixing indices were higher than 0.9. In summary, the current device with simple fabrication presents high pumping capability and mixing efficiencies even at low excitation voltages. These characteristics are all favorable for the integration in a microfluidic system.