Study on the quantitative law of wall pressure caused by mini-charge underwater explosion bubble

The wall pressure caused by underwater explosion is always a key problem in the anti-explosion design of naval ships. Notably, the accurate wall pressure caused by underwater explosion bubble is one of the most difficult parts due to the significant nonlinear deformation of the bubble. In present study, the dynamics of an underwater explosion bubble near a rigid wall are captured by high-speed camera and the wall pressure in the wall center are measured by a pressure transducer. The wall pressure with standoff distance parameter gamma = d/R-m from 0.38 to 1.54 are recorded, where d represents the vertical distance from the explosive charge center to the wall center, and R-m is the maximum radius of bubble. According to the previous study and the experimental data in this paper, when gamma < 1.2, the load on the wall center has obvious double-peak phenomenon, that is, the composition of the re-entrant jet load and the bubble collapse load. To obtain the quantitative law of wall pressure caused by mini-charge underwater explosion bubble, we proposed a mathematical model to describe the time-pressure curve when gamma < 1.2. And according to the conclusion in our previous study (Chen et al., 2018), based on the boundary element method (BEM), the space distribution of the wall pressure was obtained.