深潜器钛合金耐压壳蠕变屈曲强度评估方法研究  

Research on Assessment Method of Creep Buckling Strength of Titanium Alloy Pressure Shell for Deep-sea Submersible

作　　者：郭育豪 刘刚[1,2] GUO Yuhao;LIU Gang(School of Naval Architecture,Dalian University of Technology,Dalian 116024,China;State Key Laboratory of Structural Analysis,Optimization and CAE Software for Industrial Equipment,Dalian 116024,China)

机构地区：[1]大连理工大学船舶工程学院,大连116024 [2]工业装备结构分析优化与CAE软件全国重点实验室,大连116024

出　　处：《中国造船》2024年第2期25-36,共12页Shipbuilding of China

基　　金：国家自然科学基金面上项目(52371303,51879038)。

摘　　要：深潜器钛合金耐压壳存在室温蠕变现象,会减弱耐压壳结构的屈曲极限强度,发生蠕变屈曲破坏。论文以钛合金圆柱形耐压壳为研究对象,考虑结构初始缺陷幅值、蠕变载荷和蠕变时间的影响,通过数值模拟研究蠕变变形对耐压壳非线性屈曲强度的影响。研究表明:蠕变变形会加剧结构初始缺陷的幅值,减弱耐压壳结构的非线性屈曲强度。另外,钛合金耐压壳存在蠕变屈曲现象,蠕变屈曲的临界时间对结构初始缺陷幅值极为敏感。建立了钛合金耐压壳室温蠕变屈曲临界时间与蠕变载荷之间指数关系的模型,可以快速评估深潜器在指定作业时间下的最大下潜深度。对于不同临界时间下的蠕变载荷,该模型拟合结果与数值计算结果的相对误差均在±2%以内。Titanium alloy pressure shell of deep-sea submersible suffers from room-temperature creep,which can weaken the buckling ultimate strength of the pressure shell structure and lead to creep buckling failure.The paper takes titanium alloy cylindrical pressure shell as research object.Effects of initial imperfection amplitude,creep load,and creep time are considered,and influence of creep deformation on the buckling ultimate strength of pressure shell is investigated with numerical simulation.It is shown that the creep deformation exacerbates the magnitude of initial imperfection and weakens buckling ultimate strength of the pressure shell structure.In addition,creep buckling occurs in titanium alloy pressure shell.The critical time of creep buckling is extremely sensitive to the initial imperfection amplitude.An exponential model is proposed between room-temperature creep buckling critical time and creep load of titanium alloy pressure shell,which can be applied to quickly assess the maximum dive depth at a specified operating time.Relative errors between the fitting results of the proposed model and those of numerical calculations are all within±2%.

关 键 词：钛合金 耐压壳 室温蠕变 蠕变屈曲 极限强度 数值模拟 

分 类 号：U661.4[交通运输工程—船舶及航道工程]