Experimental Study of Flow Characteristics of Distilled Water under Pressure Driven in Microchannel

The micro-flow systems have been extensively introduced into the micro-devices in Microelectromechanical System(MEMS), and the flowing characteristics determines the performance of the micro-devices to a great extent. Here, the experiments of characteristics of distilled water flow in a series of round quartz microchannels with the diameters of 13mum, 20mum and the lengths ranging from 40 mm to 100 mm under pressure-driving force were investigated, and the relationship between the flow rates and pressure was investigated as well. The results indicate that the difference occurred in the measurement between experiment and theory for the diameter of 20 mum, the relationship between the flow rates and pressure was linear, but the experimental flow rate less than predicted, and the flow characteristics of the microchannels is basically in agreement with the macroscopic liquid flowing laws, and the same case is for the microchannels of the 15 mum in diameter with their lengths less than 70 mm. However, the flow rate is almost 2.19-3.93 times bigger than the calculated values macroscopically when the length exceeds 80 mm, which is ascribed to the occurrence of boundary slip on channel walls