水平管内气液两相泡状流壁面切应力的实验测量

Experimental measurement of the wall shear stress in horizontal air-water bubbly flow

利用TSI-1268W热膜探针测量了内径为35mm的水平管内气液两相泡状流的壁面切应力,得到了充分发展段上壁面切应力沿周向的分布数据。测量结果表明,液相中加入气泡后,在管道下部的壁面切应力增大,在含气率较高的管道上部出现了壁面切应力减小的现象。随着气相流速的增加,管道上部的壁面切应力有较小幅度的降低,管道中下部的壁面切应力有较大幅度的增加。

Experiments were carried out to measure the wall shear stress （WSS） of air-water bubbly flow in a horizontal tube with 35ram I.D. with TSI-1268w hot-film probes, and the circumferential distributions of the WSS in developed regions were obtained. The measurement shows that the addition of gas into the flows increases the WSS at the bottom wall, while decreases the WSS at top wall where the bubble population is high. With an increase of gas flow rate the amount of WSS decrease at the top wall is small, while the increase of WSS at the middle and bottom wall is apparent.