Numerical simulation on the characteristics of interface breakup and entrained bubble distribution around ship under quasi-stationary state

Due to the interaction between the hull and fluid, a wide range of interface breaking occurs around the ship. For the interface breakage around the sailing ship, the numerical simulation method is used to study the interface breakage characteristics and the distribution characteristics of entrained bubbles under the quasi-steady state. The momentum-conservation volume of fluid method is adopted to capture the two-phase interface. The governing equation is based on the incompressible Navier–Stokes equations. The octree adaptive refinement mesh is adopted to refine the two-phase interface. The simulation results can well reproduce the scars, bow wave overturning breaking, and wake interface breaking in the real environment. Through the numerical simulation of the water surface breaking around the ship model with three different Froude numbers, the characteristics of interface breaking, flow field, and bubble evolution are studied. For the bubble distribution characteristics, based on the bubble distribution in the range of the ship model, the simulation results show that the bubbles at different speeds present the phenomenon of bubble sweepdown, the fan-shaped bubble region, and the obvious bubble transport from bow to stern. And the bubbles present obvious symmetrical distribution along the width direction.