In this study, we perform a series of numerical calculations on two vessels in the time domain. One vessel maintains its position using an internal turret and catenary mooring lines, while the other is moored to the f...In this study, we perform a series of numerical calculations on two vessels in the time domain. One vessel maintains its position using an internal turret and catenary mooring lines, while the other is moored to the former vessel via an STS (ship-to-ship) mooring system. We obtain hydrodynamic forces using the HOBEM (higher-order boundary element method). Then, we determine their coefficients using the convolution function method in the time domain. We model the catenary mooring lines using the finite element method, and the STS mooring lines are treated as linear SPs (springs) with constraints. To optimize the STS system, we conduct parametric studies on STS mooring systems. Finally, we compare the motion and structural responses of the initial and modified configurations.展开更多
This paper describes the characteristics of liquefied natural gas (LNG) carriers briefly. The LNG carrier includes power plant selection, vapor treatment, liquid cargo tank type, etc. Two parameters fuel substitutio...This paper describes the characteristics of liquefied natural gas (LNG) carriers briefly. The LNG carrier includes power plant selection, vapor treatment, liquid cargo tank type, etc. Two parameters fuel substitution rate and recovery of boil of gas (BOG) volume to energy efficiency design index (EEDI) formula are added, and EEDI formula of LNG carriers is established based on ship EEDI formula. Then, based on steam turbine propulsion device of LNG carriers, mathematical models of LNG carriers' reference line value are established in this paper. By verification, the EEDI formula of LNG carriers described in this paper can provide a reference for LNG carrier EEDI calculation and green shipbuilding.展开更多
文摘In this study, we perform a series of numerical calculations on two vessels in the time domain. One vessel maintains its position using an internal turret and catenary mooring lines, while the other is moored to the former vessel via an STS (ship-to-ship) mooring system. We obtain hydrodynamic forces using the HOBEM (higher-order boundary element method). Then, we determine their coefficients using the convolution function method in the time domain. We model the catenary mooring lines using the finite element method, and the STS mooring lines are treated as linear SPs (springs) with constraints. To optimize the STS system, we conduct parametric studies on STS mooring systems. Finally, we compare the motion and structural responses of the initial and modified configurations.
基金Foundation item: Supported by the National Special Fund for Agro-scientific Research in the Public Interest (No.201003024), and the National Natural Science Foundation of China (No.51409042 No. 51209034).
文摘This paper describes the characteristics of liquefied natural gas (LNG) carriers briefly. The LNG carrier includes power plant selection, vapor treatment, liquid cargo tank type, etc. Two parameters fuel substitution rate and recovery of boil of gas (BOG) volume to energy efficiency design index (EEDI) formula are added, and EEDI formula of LNG carriers is established based on ship EEDI formula. Then, based on steam turbine propulsion device of LNG carriers, mathematical models of LNG carriers' reference line value are established in this paper. By verification, the EEDI formula of LNG carriers described in this paper can provide a reference for LNG carrier EEDI calculation and green shipbuilding.