Hydrodynamic Performance Of The Fluid Inside The Vessel Moonpool In Wave Conditions

The dynamics of flow inside moonpool is a crucial issue affecting drilling as well as launching or recovery operations at sea for most offshore drilling vessels.This paper investigates the moonpool dynamics of drilling vessel recently designed for deepwater operation.One of the features is the large moonpool opening(45.6m length and 11.2 m)for the vessel of 180.8m length.Experiments have been conducted in deepwater offshore basin at Shanghai Jiao Tong University.Comprehensive numerical simulations are carried out using the numerical model validated by the experimental data.This paper uses both potential flow theory and the CFD numerical simulation method.The flow dynamics inside moonpool including free surface elevations and water motions are examined in detail.The coupling effects between the moonpool flow and external flow,as well as the vessel motions are further investigated.(1)When the incident wave is settled down,the wave elevation in the back of the moonpool is obviously larger than it in the middle.(2)As the period of the incident wave increases,the period and the amplitude of movement of the fluid inside the moonpool increase.(3)When the period of the incident wave comes to the resonant period,the amplitude of the movement of the fluid inside the moonpool reaches the peak.(4)In addition,we can find that the coupled movements can aggravate the movement of the fluid inside the moonpool.