矩形微通道中流动阻力特性的实验研究

以蒸馏水作为工质,实验研究了水力直径为107.76~199.07m矩形紫铜微通道内的流动特性.实验中的紫铜微通道是由晶体生长法直接生长密封而成,有别于以往相关实验中刻蚀或微机加工所形成的微通道,避免了传统微通道加工方法所引入的误差,从而确保了微观尺寸的测量精度.实验测量了Reynolds数在70到1400之间摩擦阻力系数.实验结果表明:当Re数小于300时,在实验误差内,摩擦系数的值近似等于经典理论计算值;随着Re数的增大,的值大于理论值,这可能是由微通道内部壁面粗糙度效应所导致的.

Experimental Study on Flow Characteristic in Rectanglar Micro Channels

An experimental study is conducted to explain the flow characteristic, as distilled water flows through red copper microchannels with inner diameter ranging from 107.76 m to 199.07 m. Differing from conventional way of machining, such as etching or micro-machining, the experimental red copper microchannel is formed by the crystal growth, which reduce the manufacture errors. Reynolds number varied in the range from 70 up to 1 400 in the present experiment. The experiment results clearly show that the friction factors approximately agree with that of classical theory when Reynolds number is below 300 considering the experimental uncertainties. With the increase of Reynolds number, the friction factors are larger than the classical laminar solutions due to the roughness effect.