Coupling analysis of liquid sloshing and box sway motion under irregular wave actions

The coupling effect between the internal fluid sloshing and the box sway motion under irregular wave action is studied in this work. For describing external wave and internal sloshing actions, a hybrid numerical method combining linear potential flow and viscous flow is adopted. Numerical simulations show that coupling sloshing action plays an important role around sloshing natural frequencies. The significant resistant and enhanced actions can be observed at the frequencies around sloshing natural frequencies in regular waves. However, the above coupling effect approaches weak under irregular wave actions. The phase relation between the internal sloshing forces and external wave forces in regular waves cannot be found under irregular wave actions, which is the main reason for the decreased coupling sloshing effect. In all, the sway motion responses between irregular and regular wave actions show evident different behaviors from each other.