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Bubble collapse is one of the leading causes for the cavitation erosion of submerged structures. For better understanding of the destructive mechanism of cavitation, high-fidelity simulation is performed to simulate the complete process of single bubble collapse near a planar solid wall. The wave propagation method with the approximate Riemann solver Harten Lax and van Leer Contact is adopted to solve the compressible two-phase five-equation model. We implement fifth-order weighted essentially non-oscillatory scheme with the block-structured adaptive mesh method to resolve shock waves and moving interface with high-resolution. We simulate single bubble collapsing in free-field to validate the present numerical methods and solver. Our results (e.g., averaged bubble-interior pressure and the radius variation) are found in excellent agreement with the theoretical Keller–Miksis solutions. In this study, the shock wave transmitted inside the bubble and the water-hammer shock formed in the liquid are under quantitative investigation. Numerical results reveal that the interactions between the shock wave and bubble interface give rise to peak pressures of liquid phase, and the initial stand-off distances have important influence on shock wave pattern, wall peak pressure, and bubble dynamics.

The hydrodynamic problem of the water entry of wedges with oblique velocity has been investigated numerically. The simulations of the interaction of the wedge and initial calm surface are carried out by solving the Reynolds-averaged Navier-Stokes equations (RANS). The overset mesh technique is introduced and the air-water interface is tracked using the method of Volume of Fluid (VOF). The water entries of wedges with various deadrise angles at different oblique velocities are simulated. A noticeable vortex flow and low pressure area on the leeward side of the wedge have been observed. The evolution of vortex and the pressure distribution over the wedge surface are analysed. The local vortex flow affects the local hydrodynamic pressure significantly.

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