Liquid Natural Gas resource development is often conducted worldwide. Recently the drilling area has gradually expanded from shallow sea area to the deep ocean. A Floating LNG facility (FLNG) and a LNG carrier ship (LNG) are assumed to operate in the open sea expected to wind, wave and current. In this situation, an operational capability evaluation of the LNG would be needed to grasp the operational weather limitation. The effect of each weather element, i.e. wind, wave and current, giving manoeuvring effect to ships, is expected to assess exactly as external loads. In such a situation, wind interaction effect under the operating condition that a FLNG and a LNG are in same closed area is not clearly understood. This paper treats and proposes one estimation method of wind load for the operation of side-by-side offloading including interaction effect of a FLNG and a LNG. The proposed wind load estimation method based on the wind tunnel experiments represents the shielding effect of the LNG behind the FLNG. Operational assessment on ship manoeuvring under strong wind is calculated using the proposed wind load method in the final stage.

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This paper aims to understand the kinetic characteristics and the hydrodynamic forces on a semi-planing typed high-speed vehicle during moving straight in calm water and in head waves. One of the features of this vehicle is considerable variation in its attitude due to the changes in the resistance value and propulsion performance associated with the change in a Froude number of the vehicle, and no reliable method has been established to evaluate this feature in advance. Therefore, we conducted free/captive towing tests at Froude numbers ranging from 0.03 to 1.8 using a scale model of the vehicle. The results show that the vehicle can move straight stably without unstable vibration even at high Froude numbers. In addition, we performed 3D unsteady RANS (Reynolds-Averaged Navier-Stokes equation) simulations for the vehicle with Froude numbers of 0.9, 1.2, and 1.8 in calm water and found that the RANS simulation could reproduce the experimental results relatively well with respect to the vehicle’s attitude, the drag coefficient, and the free surface shape around the vehicle.

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