双舷侧结构耐撞性能影响因素研究及优化分析

发布时间：2018-05-26 08:20

本文选题：船舶碰撞 + 双舷侧结构　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：人们对海上资源的逐渐重视使航运业得到了相应的快速发展。而航线密度增大,加之天气以及人为等因素的影响导致船舶碰撞事故频发。船舶作为一种复杂而庞大的海上移动建筑物,一旦发生碰撞事故,所带来的后果十分严重,极有可能导致人员的伤亡,船体结构的破损以及严重的环境污染。因此对船体结构的耐撞性问题进行研究,寻求增强其耐撞性的方法具有极其重要的意义。碰撞问题的强非线性特点导致其求解难度增加,本文碰撞问题的数值模拟分析选用ANSYS/LS-DYNA显示动力有限元分析软件。从船舶典型构件加筋板架结构碰撞问题的分析入手,完成本文分析方法的验证。同时根据加筋板架结构在碰撞过程中的变形情况对其力学模型进行简化,运用塑性力学等相关知识推导碰撞力的简化解析公式。经过验证,该公式具有一定精度,可用于对加筋板结构的碰撞问题进行初步计算。根据所确定的有限元分析方法,以某30万吨级VLCC船舶为研究对象,完成双舷侧结构碰撞模型的建立。分析在碰撞过程中各构件的吸能和损伤变形等情况。同时分析在不同工况下双舷侧结构所体现出的耐撞性差异,讨论外在因素的变化对双舷侧结构碰撞的影响。对增强船舶耐撞性的方法进行总结概述,将其中通过改变构件几何尺寸的方式等效为双舷侧结构几何参数的变化,将在双舷侧结构内部填充材料以及在双舷侧结构外部设置护舷装置这两种通过使用耐撞性材料来增强结构耐撞性的方式等效为双舷侧结构材料参数的变化,同时考虑到不同构件在碰撞过程中表现出的不同的耐撞能力以及耐撞性材料的敷设位置会对耐撞性能产生不同影响,分别讨论了在双舷侧结构中当不同构件的几何参数与材料参数发生变化时对整体结构耐撞性产生的影响。根据双舷侧结构各参数的改变所引起的耐撞性变化情况,以结构比吸能的最大值为优化目标,分别以各构件的弹性模量、屈服应力以及几何参数为优化变量,选取响应面优化方法并结合适当的试验设计方法对双舷侧结构的耐撞性进行优化分析,得到相应约束区间内不同构件各项参数的最优解,提出增强双舷侧结构耐撞性的优化方案。
[Abstract]:People pay more and more attention to marine resources, which makes shipping industry develop rapidly. The increase of route density and the influence of weather and human factors lead to frequent collision accidents. As a complex and huge moving building on the sea, once a collision accident occurs, the consequences are very serious, which may lead to casualties, damage to the hull structure and serious environmental pollution. Therefore, it is of great significance to study the crashworthiness of hull structure and to seek ways to enhance its crashworthiness. The strong nonlinearity of the collision problem makes it more difficult to solve. In this paper, the ANSYS/LS-DYNA display dynamic finite element analysis software is used for the numerical simulation and analysis of the collision problem. Based on the analysis of the collision problem of ship's typical stiffened slab-frame structure, the analysis method of this paper is verified. At the same time, the mechanical model is simplified according to the deformation of stiffened plate-frame structure in the course of impact, and the simplified analytical formula of impact force is deduced by using the relevant knowledge of plastic mechanics. It is proved that the formula has a certain accuracy and can be used to calculate the collision problem of stiffened plate structure. According to the established finite element analysis method, a 300,000-ton VLCC ship is taken as the research object, and the collision model of the double-side structure is established. The energy absorption and damage deformation of each component during impact are analyzed. At the same time, the crashworthiness difference of the double side structure under different working conditions is analyzed, and the influence of the external factors on the impact of the double side structure is discussed. The methods of enhancing ship's crashworthiness are summarized, in which the change of the geometric size of the components is equivalent to the change of the geometric parameters of the double-side structure. The two ways in which the internal filling material of the double side structure and the fender installation outside the double side structure are equivalent to the change of the material parameters of the double side structure by using the crashworthiness material to enhance the crashworthiness of the structure, At the same time, considering the different crashworthiness of different components during the impact process and the location of crashworthiness materials, the crashworthiness will be affected differently. The effects of different geometric and material parameters on the crashworthiness of the whole structure are discussed respectively. According to the change of crashworthiness caused by the change of the parameters of the double-side structure, the maximum energy absorption of the structure is taken as the optimization objective, and the elastic modulus, yield stress and geometric parameters of each component are taken as the optimization variables, respectively. Selecting the response surface optimization method and combining the appropriate experimental design method to optimize the crashworthiness of the double-side structure, the optimal solution of the parameters of different components in the corresponding constraint interval is obtained. An optimization scheme for enhancing the crashworthiness of double side structures is proposed.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U661.43

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