Numerical simulation on effect of water depth to the hydrodynamic characteristics of the cylinder out of the tube

The influence of different water depths to the hydrodynamic properties of the cylinder in the process of vertical flyout of the tube was investigated by numerical simulation. The finite volume method based on the multiphase model, continuity equation, transport equations of liquid mass fraction, a dynamic mesh technique and a standard κ-ε turbulent model are adopted to solve the RANS equation in conjunction. The fluid-solid coupling problem in both of the movement boundary of the cylinder and the multiphase flow field was solved by using the numerical method. Under the influence of the gravity, the flow field affected the hydrodynamic characteristics of the cylinder was derived by using the numerical simulation. Simulation results show that different water depths affect on the trajectory of the underwater cylinder and hydrodynamic. The fluctuation reasons of different pressure drag coefficient, viscous drag resistance coefficient and toll resistance coefficient were studied by analyzing simulation results.