微柱群阻力特性实验研究

以去离子水为工质,流经直径为0.5 aim,高度分别为1.0 mm、0.75 mm、0.5 mm和0.25 mm的圆柱组成的柱群板,其宽度与长宽分别为3.5 mm和40 mm,测量通道进出口压差及流量,研究微柱群内部分别在叉排和顺排时液体流动的阻力特性.研究表明,微柱群内流动阻力系数f,随Re数的增大而逐渐减小,当Re数大于500时,f基本不变;微柱高度和直径之间存在一个有利于流动的最佳比例,该值介于1到1.5之间;顺排微柱群的f明显小于叉排微柱群,其,值为叉排微柱群的0.5倍.

EXPERIMENTAL INVESTIGATION OF RESISTANCE CHARACTERISTICS IN MICRO PIN FINS

De-ionized water used as working fluid flows through micro pin-fins plates with a width of 3.5 mm and a length of 40 mm made up of micro pin-fins with diameter of 0.5 mm and heights of 1.0 mm.0.75 mm,0.5 mm and 0.25 mm,respectively.The flow rate and the pressure drop between the inlet and the outlet of micro pin-fins plates are measured and the resistance characteristic of micro pin-fins plate at staggered array and in-line array is experimental investigated.The experimental results indicate that the friction factor decreases with an increase of the Reynolds number when Reynolds number is small and friction factor is approximately constant at Re>500.An optimal ratio of the height to the diameter of the micro pin-fins plate to make flow resistance least is about from 1 to 1.5 and friction factor at in-line array is approximately 0.5 times less than that at staggered array in the similar flow condition.