基于BLS的载重量38000t散货船尾部总段整体吊装优化设计

泰州口岸船舶有限公司采用整体吊装工艺对散货船尾部总段进行吊装,考虑其结构的复杂性,应用有限元法计算整体吊装时的结构强度。采用BLS软件构建船体有限元模型,计算整体吊装时的结构响应,校核结构薄弱部位,有针对性地提出加强方案并对方案的可行性进行评估。实船尾部总段的顺利吊装表明该整体吊装工艺设计合理,对后续船体尾部总段吊装具有指导和借鉴意义。     

巨型总段吊装中的有限元方法应用

介绍万m3级耙吸挖泥船总段吊装中的有限元方法应用。该挖泥船将机舱区域至艉部合成一个巨型总段建造,设备搭载后总重2300余t。为确保该总段的吊装安全,应用有限元方法分析整体吊装时的结构响应,为总段吊装及排装方案的制定提供理论依据,保证吊装工作的顺利完成。     

三维技术在船舶结构生产设计中的应用

以某滚装型船舶首门、首总段结构整体建造工艺设计过程为例，结合应用CADDS5三维设计软件和相关的软件系统进行该船首门、首总段结构三维模型设计、通道装置间的运动分析仿真、首门装配工艺数据计算以及工艺工装设计方面的应用，介绍三维设计技术在复杂船舶结构生产设计中的应用方法。     

沪通铁路大桥沉井总段整体吊装强度有限元分析

利用MSC.Nastran软件对沪通铁路大桥沉井总段吊装前和吊装工况下结构在自重作用下的响应进行了有限元分析,合成得到了吊装引起的结构响应.计算分析表明文中提出的吊装方案可行,结构响应满足强度要求.通过有限元计算分析得到的有关结论可用于指导吊装方案的设计及优化;根据结构响应的特点可提出合理有效的结构加强措施,保证整体吊装的顺利完成.     

基于TSV-BLS软件客滚船机舱总段整体吊装方案分析

考虑到客滚船机舱总段结构的复杂性,为确保吊装安全,使用TSV-BLS软件构建总段有限元模型,计算整体吊装时总段的应力和变形、钢丝绳的拉力等,并对吊装方案的可行性进行评估。实船顺利吊装证明该吊装方案设计合理,对于其他船舶机舱总段的吊装具有一定的指导和借鉴。     

船舶建造总段吊装方案分析

本文以中机型船舶机舱分段为例,对船舶建造过程中总段吊装方案进行分析,并通过有限元计算对吊装过程中的应力应变进行了研究。通过本文分析,对总段吊装方案的策划进行了介绍,为船舶建造过程中的总段吊装提供有利的借鉴意义。     

64000载重吨散货船上层建筑总段吊装强度分析

针对64 000载重吨散货船上层建筑总段在吊装过程中可能出现强度不够的情况,应用有限元软件评估其实际吊装方案。该方案首先利用MSC. Patran软件建立64 000载重吨散货船上层建筑总段有限元模型,其次应用MSC. Nastran分析总段在整体吊装前和吊装时的结构响应,得到总段由吊装过程引起的结构响应。结果表明:上层建筑总段的结构强度满足吊装要求,证明吊装方案安全可行。     

5300TEU集装箱船上层建筑总段吊装强度分析

通过MSC.Nastran软件对5300TEU集装箱船上层建筑PM61C总段进行吊装强度有限元分析,分析了总段在吊装前和吊装时的结构响应。通过计算得到总段由吊装引起的结构响应,并计算分析吊耳的结构响应,保证上层建筑总段吊装过程顺利进行。     

半潜式钻井平台总段吊装强度数值计算

半潜式钻井平台因结构复杂和设备繁多,对建造周期提出了更高的要求。实现总段吊装大型化,提高吊装前的预舾装程度,这对提高生产效率、缩短平台建造周期、降低平台建造成本具有十分重要的意义。应用有限元数值计算分析技术,对吊装状态下平台大型总段的结构响应(应力与变形)进行研究,通过分析各总段构件的结构强度,对吊装方案进行评估,并对平台大型总段吊装提出一些建议和措施。     

基于有限元方法的大型邮轮薄板总段吊装方案设计

考虑到大型邮轮薄板总段使用大量薄板结构,而薄板结构在吊装过程中极易产生变形,在对总段吊装进行方案设计时,利用MSC Patran/Nastran对薄板总段吊装方案进行有限元计算,确定合理的吊装及临时加强方案。     

Bow door slamming of Ro/Ro ferries

This paper addresses the structural response of clam-type bow doors of Ro/Ro vessels under slamming loading conditions. The structural analysis is performed with the finite element code MSC/NASTRAN. The loading conditions were determined on the basis of towing tank tests, numerical calculation and regulations of classification societies. Slamming loads are applied statically and the FE code accounts for both material and geometrical nonlinearities. Apart from stress distributions, which are determined for different loading patterns, the results are used to calculate the forces and moments induced on the locking and securing elements, which secure the doors among themselves and the doors to the bow structure. The modelling methods reported may be used for the finite element analysis of similar structures. Such analyses of bow doors response under slamming loading could be submitted to classification societies for approval.     

船舶首部结构装配序列的模糊评价研究

该文通过对船舶首部结构装配工艺的分析研究,提出了船舶首部结构装配序列评价指标体系;针对指标体系所具有的特点,采用层次分析法和模糊综合评价法(多层次模糊综合评价法)对船舶首部装配序列进行了分析研究,并获得船首部装配序列总体评价结果。该评价方法有助于提高船首部装配序列优选的自动化水平。     

Prediction and mitigation of out-of-plane welding distortion of a typical block in fabrication of a semi-submersible lifting and disassembly platform

Out-of-plane welding distortions of block structures during fabrication of offshore structure will significantly influence its dimensional accuracy and production schedule. Taking a B514 block of a semi-submersible lifting and disassembly platform as research object, typical welded joints and their welding conditions were summarized based on actual welding procedure specification (WPS). Effective thermal elastic plastic (TEP) finite element (FE) analysis with parallel computation technology was carried out to examine thermal-mechanical response. Welding inherent deformations, which are considered as the elementary cause of welding distortion, were then evaluated. With welding inherent deformations as mechanical loading, elastic finite element (FE) analysis was then employed to predict dimensional accuracy of examined B514 block, which has a good agreement with measurement data. In order to ensure the fabrication accuracy with less out-of-plane welding distortion, inverse deformation approach was applied to reduce the out-of-plane welding distortion, and influence of welding sequence on out-of-plane welding distortion was also examined. Both mitigation practices have obvious effect on dimensional accuracy of examined B514 block, while corresponding mechanical mechanisms were also clarified.     

大型VLCC上层建筑整体吊装有限元分析

针对大型船舶上层建筑整体吊装过程中的变形控制问题,以某大型VLCC为研究对象,利用MSC.Nastran有限元软件对其上层建筑结构进行整体吊装强度有限元分析,得到各层结构响应,据此提出结构加强措施,有效降低了结构应力和变形。     

Local structural response to seakeeping and slamming loads

A common approach to investigate the response of a structural detail such as a hatch corner is to compute the seakeeping loads using a linear 3D Boundary Element Method (BEM) and transfer the seakeeping loads to a Finite Element (FE) model of the ship structure. This approach is suitable for computations of the fatigue loading of structural details near amidships because a majority of the fatigue loading will occur in mild sea-states where the loading may be assumed linear. However, the linear seakeeping model may not hold when one investigates the ultimate response of the local bow structure of a ship which is designed to remain operational in severe conditions, for example, a frigate. A linear seakeeping analysis will significantly underpredict the loading at the bow because both the impulsive slamming loads and the non-linearities in the non-impulsive wave loads will contribute significant to the structural loading.The non-linear loads require one to first derive a short-term distribution of the local structural response before the ultimate value of the response can be derived. A method to compute the short-term distribution of a structural detail is presented in this paper. The first step is to perform seakeeping analyses which includes slamming, non-linear Froude-Kryloff and hydrostatic loads. The short-term distribution of the total hydrodynamic loading at the structural detail is obtained by simulating the seakeeping response for several hours. The response of the local structure is computed for the most severe impacts found in the seakeeping simulation. The hydrodynamic loading, including the non-linear contributions, is transfer to the structural model and the structural response is computed using the FE-method. The results of the structural analyses allow one to transform the short-term distribution of the structural loading to a short-term distribution of the response of the structural detail. A designer can obtain the ultimate structural response by entering the probability at which one accepts overloading of the structure in the short-term distribution of the response of the structural detail.     

基于整船整桥模型的船桥碰撞数值仿真

桥梁在船舶碰撞时受到的动力载荷和响应是复杂的动力非线性问题。近代非线性有限元技术为该问题的求解提供了有效的工具。本文简述了该技术的基本原理，并基于整船整桥模型，对一艘4万吨实船与桥梁的碰撞过程进行了计算。仿真结果显示了船艏结构损坏、碰撞力演变、能量传递和桥墩内部应力变化的详细情景，讨论了船—桥碰撞的力学特征。本文演示的方法比传统的经验公式和简化解析法提供了更为精确的结果。所提供的桥墩应力状态对桥梁的设计与碰撞后的损伤评估有重要参数价值。     

柔性、刚性球艏对双壳舷侧结构耐撞性能影响的研究

采用非线性显示动力有限元软件LS_DYNA,对舷侧双壳结构在柔性和刚性球艏撞击下的动力响应进行仿真研究.采用全船有限元模型,考虑船体周围附连水质量对结构动力响应的影响.给出了碰撞力-撞深、能量-撞深曲线以及各构件吸收的能量.仿真结果表明:不同球艏撞击下舷侧内外壳板的破裂时刻、撞深和舷侧结构变形性能都有所不同.     

Numerical study on the dynamic response of a truncated ship-hull structure under asymmetrical slamming

Dynamic response of ship-hull structure under slamming has tracked widespread attention in the marine structural design. However, our understanding on the dynamic characteristics largely relies on the symmetrical slamming cases. This paper presented a preliminary numerical investigation on the dynamic response of a truncated ship-hull structure under asymmetrical slamming based on the uncoupled CFD-FE method. Asymmetrical slamming loads were predicted through combining the seakeeping analysis and CFD method. In there, three kinds of motions (vertical, horizontal and roll motions) of 2D ship sections were obtained through the seakeeping analysis and then the slamming pressure was predicted through simulating the water entry with various motions based on CFD method. The dynamic response was analyzed through finite element method. Numerical predictions including ship motions, slamming loads and dynamic analysis were validated against published experimental data and numerical calculations. The characteristics of asymmetrical slamming loads were analyzed showing obvious asymmetry in space, and the dynamic characteristic of the ship bow structure was further clarified through discussing the deformation and stress distribution. These results are useful for readers for better understanding the dynamic characteristics of the bow structure under slamming.     

单/双壳体潜艇结构耐撞剩余强度特性研究

单/双圆柱壳体结构是潜艇的两种典型结构形式.以单/双壳体潜艇典型结构为研究对象,分别设计初始深水静压强度相当的典型单/双耐压环肋圆柱壳体结构模型,基于MSC/Dytran罚函数接触算法,开展相同撞击强度载荷作用下结构模型耐撞动态响应特性分析,提取撞击后结构模型中耐压壳体结构的稳定变形位移场,作为MSC/Marc静强度求...