﻿ 钛合金耐压壳在碰撞下的动力屈曲数值模拟
 舰船科学技术  2021, Vol. 43 Issue (12): 55-58    DOI: 10.3404/j.issn.1672-7649.2021.12.010 PDF

1. 江苏科技大学 船舶与海洋工程学院，江苏 镇江 212003;
2. 江苏科技大学 土木工程与建筑学院，江苏 镇江 212003

Numerical simulation of titanium alloy pressure shell′s dynamic buckling under collision
WANG Lin1,2, LIU Zhen1,2, LIU Ping1,2
1. School of Naval Architecture and Ocean Engineering, Jingsu University of Science and Technology, Zhenjiang 212003, China;
2. School of Civil Engineering and Architecture, Jingsu University of Science and Technology, Zhenjiang 212003, China
Abstract: When the submersible is sailing, it may collide with reefs, icebergs, other submersibles, etc. The collision will cause damage, deformation, and buckling of some submersible structures. In recent years, the dynamic buckling of pressure-resistant structures under collision has attracted the attention and research of many scholars. In this paper, the finite element software Ansys/Ls-dyna is used to study the dynamic buckling of a titanium alloy pressure shell under collision. The result of impact velocity on the dynamic buckling of the pressure shell shows that the ratio of the maximum collision force to the average collision force during the collision may be unchanged before the impact velocity reaches the buckling of the pressure shell; The impact speed is almost linearly related to the maximum collision force and the average collision force before the impact velocity reaches the buckling of the pressure shell, Without considering the influence of other factors (thickness of the pressure shell, elastic modulus, hydrostatic pressure, etc.) on the collision force.
Key words: pressure shell     collision     dynamic buckling     titanium alloy
0 引　言

1 钛合金耐压壳有限元模型

 图 1 耐压结构碰撞模型 Fig. 1 model of pressure structure collision

2 动力屈曲判定准则

 图 2 不同撞击速度下耐压壳位移-时间曲线 Fig. 2 Displacement-time curve of pressure shell under different impact speeds
3 平均碰撞力的求解

 图 3 碰撞力-时间曲线 Fig. 3 Collision force-time curve
 $I_{m}=\int_{t_{1}}^{t_{2}} f(t) {\rm{d}} t, f_{m}=I_{m} / \Delta t。$ (1)

4 撞击速度对钛合金耐压壳动力屈曲的影响

 图 4 不同厚度下碰撞力-速度关系图 Fig. 4 Collision force-speed relationship under different thickness

 图 5 厚度分别为35 mm，45 mm时不同撞击速度下碰撞力-时间曲线 Fig. 5 Impact force-time curve at different impact speeds at 35 mm, 45 mm thickness

5 结　语

1）在撞击速度达到使耐压壳发生屈曲前，碰撞过程中的最大碰撞力与平均碰撞力的比值可能不变。

2）在不考虑其他因素（耐压壳的厚度，弹性模量，静水压力等）对碰撞力的影响的前提下，撞击速度在达到使耐压壳发生屈曲前，与最大碰撞力和平均碰撞力近乎呈线性关系。

3）保持其他参数不变，厚度较大的耐压壳，碰撞的持续时间较短。

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