The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier...The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier's response in waves. In this work, experimental and numerical assessments of the motion and load response of a 550,000 DWT ore carrier are performed using prototype ships with softer stiffness, and towing tank tests are conducted using a segmented model with two schemes of softer stiffness. Numerical analyses are performed employing both rigid body and linear hydroelasticity theories using an in-house program and a comparison is then made between experimental and numerical results to establish the influence of stiffness on the ore carrier's springing response. Results show that softer stiffness models can be used when studying the springing response of ships in waves.展开更多
阐述40万吨级超大型矿砂船(Very Large Ore Carrier,VLOC)的现状,包括分析世界经济形势和贸易需求、目前VLOC的订单情况及矿商和港口航道的因素。浅析第二代40万吨级VLOC的技术要点。通过市场预测和自身要求,解读给予上海外高桥造船有...阐述40万吨级超大型矿砂船(Very Large Ore Carrier,VLOC)的现状,包括分析世界经济形势和贸易需求、目前VLOC的订单情况及矿商和港口航道的因素。浅析第二代40万吨级VLOC的技术要点。通过市场预测和自身要求,解读给予上海外高桥造船有限公司(SWS)的启示,为SWS更加顺利,保质保量地完成此次VLOC建造任务提供支撑。展开更多
为研究矿砂船的大型化与运价波动性的联系,针对国际主流铁矿石运输航线的好望角型船海运运价的时间序列,引入虚拟变量构建GARCH模型.研究发现,超大型矿砂船(Very Large Ore Carrier,VLOC)投入运营并未对主流铁矿石航线的好望角型船海运...为研究矿砂船的大型化与运价波动性的联系,针对国际主流铁矿石运输航线的好望角型船海运运价的时间序列,引入虚拟变量构建GARCH模型.研究发现,超大型矿砂船(Very Large Ore Carrier,VLOC)投入运营并未对主流铁矿石航线的好望角型船海运运价的波动性产生根本性的影响.相比图巴朗至青岛航线,图巴朗至鹿特丹航线的铁矿石海运运价更具稳定性.航运企业应根据市场需求积极优化船队结构和船舶运营市场的布局.展开更多
Investigation of hydroelastic ship responses has been brought to the attention of the scientific and engineering world for several decades. There are two kinds of high-frequency vibrations in general ship responses to...Investigation of hydroelastic ship responses has been brought to the attention of the scientific and engineering world for several decades. There are two kinds of high-frequency vibrations in general ship responses to a large ocean-going ship in its shipping line, so-called springing and whipping, which are important for the determination of design wave load and fatigue damage as well. Because of the huge scale of an ultra large ore cartier （ULOC）, it will suffer seldom slamming events in the ocean. The resonance vibration with high frequency is springing, which is caused by continuous wave excitation. In this paper, the wave-induced vibrations of the ULOC are addressed by experimental and numerical methods according to 2D and 3D hydroelasticity theories and an elastic model under full-load and ballast conditions. The influence of loading conditions on high-frequency vibration is studied both by numerical and experimental results. Wave-induced vibrations are higher under ballast condition including the wave frequency part, the multiple frequencies part, the 2-node and the 3-node vertical bending parts of the hydroelastic responses. The predicted results from the 2D method have less accuracy than the 3D method especially under ballast condition because of the slender-body assumption in the former method. The applicability of the 2D method and the further development of nonlinear effects to 3D method in the prediction of hydroelastic responses of the ULOC are discussed.展开更多
基金Supported by the National Natural Science Foundation of China （Grant No. 51079034）, and the National Basic Research Program of China （Grant No. 2011CB013703）
文摘The desire to benefit from economy of scale is one of the major driving forces behind the continuous growth in ship sizes. However, models of new large ships need to be thoroughly investigated to determine the carrier's response in waves. In this work, experimental and numerical assessments of the motion and load response of a 550,000 DWT ore carrier are performed using prototype ships with softer stiffness, and towing tank tests are conducted using a segmented model with two schemes of softer stiffness. Numerical analyses are performed employing both rigid body and linear hydroelasticity theories using an in-house program and a comparison is then made between experimental and numerical results to establish the influence of stiffness on the ore carrier's springing response. Results show that softer stiffness models can be used when studying the springing response of ships in waves.
文摘阐述40万吨级超大型矿砂船(Very Large Ore Carrier,VLOC)的现状,包括分析世界经济形势和贸易需求、目前VLOC的订单情况及矿商和港口航道的因素。浅析第二代40万吨级VLOC的技术要点。通过市场预测和自身要求,解读给予上海外高桥造船有限公司(SWS)的启示,为SWS更加顺利,保质保量地完成此次VLOC建造任务提供支撑。
文摘为研究矿砂船的大型化与运价波动性的联系,针对国际主流铁矿石运输航线的好望角型船海运运价的时间序列,引入虚拟变量构建GARCH模型.研究发现,超大型矿砂船(Very Large Ore Carrier,VLOC)投入运营并未对主流铁矿石航线的好望角型船海运运价的波动性产生根本性的影响.相比图巴朗至青岛航线,图巴朗至鹿特丹航线的铁矿石海运运价更具稳定性.航运企业应根据市场需求积极优化船队结构和船舶运营市场的布局.
基金supported by China Shipbuilding Industry Corporationthe Academy of China Ship Scientific Research Center(Grant No.62101010103)
文摘Investigation of hydroelastic ship responses has been brought to the attention of the scientific and engineering world for several decades. There are two kinds of high-frequency vibrations in general ship responses to a large ocean-going ship in its shipping line, so-called springing and whipping, which are important for the determination of design wave load and fatigue damage as well. Because of the huge scale of an ultra large ore cartier （ULOC）, it will suffer seldom slamming events in the ocean. The resonance vibration with high frequency is springing, which is caused by continuous wave excitation. In this paper, the wave-induced vibrations of the ULOC are addressed by experimental and numerical methods according to 2D and 3D hydroelasticity theories and an elastic model under full-load and ballast conditions. The influence of loading conditions on high-frequency vibration is studied both by numerical and experimental results. Wave-induced vibrations are higher under ballast condition including the wave frequency part, the multiple frequencies part, the 2-node and the 3-node vertical bending parts of the hydroelastic responses. The predicted results from the 2D method have less accuracy than the 3D method especially under ballast condition because of the slender-body assumption in the former method. The applicability of the 2D method and the further development of nonlinear effects to 3D method in the prediction of hydroelastic responses of the ULOC are discussed.
