应用高速摄影技术研究空化现象

高速摄影技术是研究空化现象的有力工具。文中利用高速摄影技术研究了液体粘性、 含沙量及流速对电火花空泡溃灭过程的影响。主要结论有：液体粘性使空泡溃灭过程变 缓；含沙量的影响类似于液体粘性：流速使空泡膨胀过程变缓但使溃灭过程加速；近固壁 处空泡溃灭时微射应朝向壁画，而当壁面具有高弹性或在自由表面附近溃灭时则微射流将 背离壁面；空泡溃灭时将使泡周围的固体颗粒产生运动。文中附有典型高速摄影照片。

Investigation of Cavitation Bubble Collapse Process by High-speed Photography

High-speed photography is an effective tool for the study of cavitation phenomenon. The effects of fluid viscosity,sediment concentration and fluid velocity on bubble collapse process as generated by electronic sparks was investigated. Main conclusions are:the viscosity of fluid tends to slow down and then prolong the process of collapse and growth ; effect of sediment concentration on bubble collapse and growth is similar to that of fluid viscosity; the fluid velocity tends to slow down the process of bubble growth but speed up the process of collapse ; the high-velocity microjet is directed to the wall when the bubble collapses near the wall ; but in the case of a highly resilient wall or free surface, the direction of high-velocity microjet will move away from the wall or the free surface; in the process of bubble collapse, the bubble wall motion would induce the motion of sediments around the bubble. Representative high-speed photogrophs are given