气泡碰壁反弹的动力学模型研究

In order to understand the physical mechanism and detailed hydrodynamic process of the interaction between bubble and rigid wall, the dynamic process of the interaction between bubble and wall was analyzed and the development of theoretical model was summarized. The numerical solution was carried out by using the theoretical model established. When a bubble on millimeter size range collided with a rigid wall vertically, a liquid film was formed between the wall and the bubble surface. The abundant and complicated film appeared in different forms. Deformation of the bubble surface would change the distribution of pressure in the film and the film drainage process occurred. The bubble rebounded several times in the process of interaction with the wall until the kinetic energy was completely dissipated. In the dynamic model established, the film thickness was described by Stokes-Reynolds equation and the pressure distribution in the liquid film was calculated by Young-Laplace equation. The wall-induced force caused by pressure was introduced into the trajectory model of bubble. The results show that the wall induced force model based on the thin film lubrication approximation can predict the trajectory of bubbles with good accuracy and reflect the dynamic process of multiple rebounds of bubbles very well. The wall induced force plays a dominant role in the bubble motion in the process of collision. With the increase of bubble size and Reynolds number, the number of bubble rebounds will increase gradually. Whether bubble rebound or not and the number of rebounds are directly related to Reynolds number.