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The hydrodynamic problems of water entry of a wedge are investigated by a modified ghost-cell immersed boundary method. The modifications correspond to a newly proposed scheme for dealing with fluid–body interaction, and incorporation of CIP (Constraint Interpolation Profile) method and THINC/SW (Tangent of Hyperbola for Interface Capturing with Slope Weighting) method. The modified ghost-cell immersed boundary method uses a compact interpolation structure and gives the fluid properties to the ghost cell to achieve a more accurate treatment of fluid–body interaction. It can preserve the sharpness of the immersed boundary. To validate the new method, simulations of water entry of symmetric and asymmetric wedges in a single degree of freedom and water entry of an asymmetric wedge in three degrees of freedom are carried out, respectively. The variations of pressure, vertical velocity, vertical acceleration, angular displacement, and angular acceleration against time are focused on. The evolution of the free surface and velocity distributions of fluid is also analyzed. The results of numerical simulations are compared with available experimental results and fairly good agreement is obtained, which indicates that the present model is reliable.

Free surface flow interaction with an elastic plate is simulated by a Constraint Interpolation Profile-based Model. A finite difference method (FDM) based on the CIP method is used for solving the flow field in a fixed staggered Cartesian grid and a finite element method (FEM) is used for dealing with the structural deformation. Beside, a volume of fluid type method, the THINC/SW (Tangent of Hyperbola for Interface Capturing with Slope Weighting) method is used to capture the free surface and a Ghost-Cell Immersed Boundary Method is adopted to couple the fluid and structure interaction. To verify the model, a rolling tank sloshing with a thin elastic plate is computed. Predicted results are found to be more agreement with the experimental results than reference data. Furthermore, two other benchmark experiments are tested, including an elastic gate deformation in dam break and a hanging elastic beam in a shallow oil sloshing. The computed results agree well with published literatures. It validates the reliability of the present solver to deal with nonlinear fluid-structure interactions.