平板湍流边界层内气泡流流动实验研究

Experimental study of bubbly flow in a turbulent boundary layer of flat plate

在低湍流度水槽里 ,利用片光源显示了平板气液两相湍流边界层内气泡流的流场结构 ,研究了平板安装位置、来流速度、喷气方式等参数对湍流边界层内气泡流的影响 .利用激光测速技术测量了平板水平放置时气泡流最外缘处的水平速度及厚度 .结果表明 :平板喷气减阻的原因在于喷气改变了平板湍流边界层的流动结构 。

The bubbly flow in air\|liquid two phase turbulent boundary layer of flat plate is visualized by the light sheet in low turbulence water tunnel.The influence of plate orientation (horizon, trim and heel), 3 free stream velocities, and 5 kinds of air injection manners on the bubbly flow is experimentally studied. The horizontal velocity at the outermost edge and thickness of bubbly flow are measured by laser Doppler velocity technique.The reduction of skin friction is related to the inhibition of turbulence in the liquid phase, owing to air injection.