复合材料船体入水砰击损伤研究

发布时间：2018-06-04 23:28

本文选题：复合材料 + 层合板模型　；参考：《哈尔滨工业大学》2016年硕士论文

【摘要】：复合材料(Fiber Reinforced Plastic,FRP)有着高的比强、刚度,优良的可设计性及抗疲劳特性等,以复合材料制造的船艇满足了对高速、低排、耐用、安适等设计理念的追求,因此被普遍应用到快艇、猎扫雷艇等民用和军用船舶领域。随着船舶高速化的发展,船体出水以后再次入水时,船体与水面之间极易出现砰击现象,致使复合材料船体局部结构发生损伤。复合材料的损伤从产生到扩展是一个渐变发生的过程,产生的各种内部细微损伤也不是凭着肉眼就能直接观察到的,因此砰击损伤的存在对FRP船艇的安全性构成了潜在威胁。根据断裂、损伤力学和FRP失效准则的相关理论,本文用有限元软件ANSYS/LS-DYNA对FRP层合板进行了建模,低速冲击FRP层合板的损伤模拟验证了该模型的正确性。结合ALE算法、水动力砰击理论完成了FRP层合板砰击损伤机理的分析,探究了FRP层合板的损伤规律。接着根据复合材料船体舱段构造形式的差异对其入水砰击响应状况进行了研究。经过比较分析,得到了抗砰击复合材料船体的可用方案,为以后复合材料船艇的抗砰击设计工作给出参考。首先,为模拟复合材料的各种损伤形式,本文采用了一种基于粘结原理的界面元模型,用应变能能量释放率准则来模拟层间损伤;单层板模型通过Change-Change失效准则和刚度退化机制来模仿层内损伤。利用FRP层合板模型从铺层方向、板厚、斜升角、入水角、入水速度等方面研究了FRP入水砰击损伤机理和失效形式。各因素对FRP层合板的损伤影响较大。然后,使用FRP层合板模型构建外板,体单元模型模拟型材结构,顺序研究了T型加筋、单向帽型加筋以及双向帽型加筋这3种常用加筋形式的FRP船艇板架的抗砰击特性,并对比分析了外板和骨架对FRP船艇抗砰击性能的不同影响。得出了外板是砰击载荷的主要承受部件。最后,从船艇舱段的骨架构造方式、骨材的尺寸和船体板的厚度三个方面探究了复合材料船体舱段的抗砰击特性。经过比较分析,得到了抗砰击复合材料船体的较优方案,对今后复合材料船艇的抗砰击设计工作来说具有参考意义。
[Abstract]:Fiber Reinforced Plastic (FRP) has high specific strength, stiffness, excellent design and anti fatigue properties. The craft made with composite materials meets the pursuit of high speed, low row, durability, and comfort, so it is widely used in the field of civil and military ships, such as fast boat, hunting Minesweeper, and so on. With the high speed of ship When the water comes into water again, the slamming between the hull and the water surface is easy to occur, which causes the damage of the local structure of the composite hull. The damage from the production to the expansion of the composite is a gradual process, and the fine internal damage is not directly observed by the naked eye, so the damage of the composite material is not directly observed by the naked eye. The existence of slamming damage poses a potential threat to the safety of FRP boats. Based on the theory of fracture, damage mechanics and FRP failure criteria, this paper uses the finite element software ANSYS/LS-DYNA to model the FRP laminates. The damage simulation of low velocity impact FRP laminates has verified the correctness of the model. Combined with ALE algorithm, the hydrodynamic slamming theory is combined. On the basis of the analysis of the slamming mechanism of the FRP laminate, the damage law of the FRP laminate is explored. Then, according to the difference of the structure form of the hull section of the composite material, the water slamming response of the composite plate is studied. After the comparison and analysis, the available scheme of the slamming composite hull is obtained, which is the anti slamming of the composite hull. In order to simulate the design work, in order to simulate various damage forms of composite materials, an interface element model based on bond principle is used to simulate interlayer damage with the strain energy release rate criterion. The layer model is modeled by the Change-Change failure criterion and the stiffness degradation mechanism to simulate the damage in the layer. The FRP laminates are used in the monolayer model. The damage mechanism and failure form of FRP water slamming are studied from the direction of layer, thickness, angle of inclined lift, angle of water entry, water entry speed and so on. Each factor has great influence on the damage of FRP laminate. Then, the outer plate is constructed with the FRP laminates model and the body element model is used to simulate the section structure, and the order of T reinforcement, unidirectional cap reinforcement and double is studied in sequence. The anti slamming characteristics of the 3 commonly reinforced FRP hull plates are reinforced, and the different effects of the outer plate and skeleton on the slamming performance of the FRP boat are compared and analyzed. The main bearing parts of the slamming load are obtained. Finally, the skeleton structure of the hull section, the size of the bone material and the thickness of the hull plate are three aspects. The anti slamming characteristics of the hull section of the composite ship hull are explored. After comparison and analysis, a better scheme is obtained for the hull of the slamming composite material, which is of reference significance for the slamming design of the composite hull in the future.
【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】：2016
【分类号】：U661.4

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