Bubble motion and jet load near elastic-plastic structure under deep-water explosion

The conclusions obtained for bubble motion and jet load in shallow water with rigid and elastic-plastic structure as boundary conditions are not fully applicable in deep water. This is because the work done by the hydrostatic pressure in the deep water environment during the dynamic deformation of the structure cannot be ignored. The combined effect of dynamic and static loads is more significant. The mode of structural damage is different from that in shallow water. The different structural responses will feed back into the fluid medium. This will lead to bubble motion and jet load in the vicinity of the structure filled with uncertainty. So, in this manuscript, the bubble dynamic behavior under different boundaries - free field, near rigid structure, near elastic-plastic structure (only large deformation or fracture after large deformation) - in the background of deep water explosion is investigated based on coupled Eulerian-Lagrangian (CEL) method. The structural response, bubble motion, and jet load characteristics are compared and analyzed for four typical scenarios. No jet, water jet, reverse water jet, and counter jet are discovered sequentially. However, in a realistic underwater explosion, structure is elastic-plastic. Therefore, the analysis focuses on dynamic behavior of bubble under the boundary of elastic-plastic structure during deep-water explosion. The dynamical behavior of bubble is found to be heavily dependent on two variables, the mode of damage of the structure (only large deformation and fracture after large deformation) and the distance parameter gamma. Further, the bubble motion and jet load characteristics are explored. Eight different forms of bubble motion are found in different combinations of the two variables. In these eight scenarios, it is possible for the bubble jet load to occur at different times and in different directions, or possibly not at all.