表面张力对单空泡运动特性的影响

Influence of fluid surface tension on the kinematic characteristics of single bubble

本文利用高速摄影技术，在摄像及电子计算机的辅助下，研究了在５种不同的表面张力（液体－空气）液体中由电火花放电所造成的空泡膨胀及收缩运动过程，记录、分析、计算了空泡的半径Ｒ．泡壁速度Ｒ及加速度Ｒ随时间的变化．结果表明：表面张力加速了空泡的收缩过程，对其膨胀过程则起了延缓作用，通过实验给出了空泡膨胀时间与收缩时间的比值．一般说来，在空泡溃灭以前，表面张力愈小的液体中，空泡泡壁的速度最大值愈大、泡壁的加速度通常具有３个极值，其最大值可达１０４ｍ／ｓ２量级，这可能是空泡在收缩过程中泡壁失稳及溃灭时产生强大的溃灭冲击压强的重要原因之一．

The effect of fluid surface tension on the process of bubble collapse and growth is investigated. The bubbles are generated by sparks.Five fluids with different surface tension are to be used. The process was revealed by High-speed photography.The main conclusions of this investigation are: the surface tension of fluid tends to slow down the process of growth and speed up the process of collapse of the bubble's, the smaller the surface tension the bigger the maximum bubbles surface velocity, the acceleration of bubble's surface has three extreme values with the maximum value as high as 104m / s2, it probably is the primary reason of unstability of bubble's surface in collapse process and causes tremendous impact.