Fully coupled model for simulating highly nonlinear dynamic behaviors of a bubble near an elastic-plastic thin-walled plate

Existing studies of bubble-structure interaction mainly focus on the interaction between a bubble and a movable rigid body or deformable linear elastic structure. The strong nonlinear interaction of a bubble with an elastic-plastic plate has rarely been studied while the inherent dynamic behavior is not clear. In this paper, we develop a three-dimensional fully coupled model to investigate the interaction between a bubble and an elastic-plastic thin-walled plate, which can consider the fluid disturbance on both sides of the thin-walled plate. In this developed model, the dynamic behaviors of the bubble are obtained by the boundary integral method based on the potential flow theory, and the nonlinear elasticplastic responses of the structure are resolved by the explicit finite element method on the basis of the Mindlin-Reissner plate theory. The structural nonlinear responses are incorporated into the fluid boundary integral equation (BIE), and the extra relation between the phi(t) (time derivative of velocity potential) jump across the two sides of the thin-walled plate and its normal derivative phi(tn) is derived, which can describe the hydrodynamic balance on both sides of the submerged plate. The derived relation is added to the BIE about phi(t), so that the bubble loading acting on the plate can be accurately calculated. The established coupled model is validated by comparing with experimental results. Using this numerical model, the influence of the standoff distance and plate thickness on the bubble-plate interaction is discussed. Subjected to the violent loading from the bubble, the oscillation characteristics and elastic-plastic deformation of the plate are analyzed. Due to the elastic-plastic effects of the plate, the bubble can display different interesting featured patterns, including attractive motion, repulsive motion, or splitting.

Automated summary

This study focuses on the interaction between a bubble and an elastic-plastic thin-walled plate, revealing that the structural nonlinear responses affect the bubble loading on the plate and result in different motion patterns and splitting phenomena. The developed three-dimensional fully coupled model enhances understanding of the dynamic behavior of the bubble-structure interaction.