Abstract The paper presents a result of the numerical investigation into the buckling behaviour of geometrically imperfect cone-cylinder transition subjected to external pressure. The models are assumed to be made from the Hiduminium alloy (HE-15). Various initial geometric imperfections such as eigenmode imperfection and Single Load Indentation (SLI) imperfections were superimposed on the perfect cone-cylinder shell. The reduction of the buckling strength was then quantified numerically. As expected, the buckling strength of cone-cylinder shells were strongly affected by initial geometric imperfection and the reduction in buckling strength was seen to be strongly dependent on the choice and location of imperfection. Overall, the lowest SLI imperfection curve produces the worst sensitivity as compared to the eigenmode imperfection curve. Conservative knockdown factors that can be implemented for the design of cone-cylinder transition have been proposed for both eigenmode imperfection and SLI imperfection. Finally, a simple empirical solution based on several case studies has been proposed that could reasonably be used to estimate the buckling of externally pressurized cone-cylinder shell transition under Geometrical and Materially Non-linear Analysis (GMNA) and Geometrical and Materially Non-linear Imperfection Analysis (GMNIA) cases. A good correlation with the ultimate strength is observed with the application of the proposed empirical formula.

中文翻译：

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外压作用下不完美锥筒过渡的屈曲

摘要 本文介绍了几何缺陷锥筒过渡在外压作用下屈曲行为的数值研究结果。假设模型由 Hiduminium 合金 (HE-15) 制成。各种初始几何缺陷，如本征模缺陷和单载荷压痕 (SLI) 缺陷叠加在完美的锥柱壳上。然后用数字量化屈曲强度的降低。正如预期的那样，锥筒壳的屈曲强度受到初始几何缺陷的强烈影响，并且屈曲强度的降低强烈依赖于缺陷的选择和位置。总的来说，与本征模缺陷曲线相比，最低的 SLI 缺陷曲线产生最差的灵敏度。已经针对本征模缺陷和 SLI 缺陷提出了可用于锥柱过渡设计的保守击倒因子。最后，基于几个案例研究提出了一个简单的经验解决方案，可以合理地用于估计几何和材料非线性分析（GMNA）和几何和材料非线性缺陷下外部加压锥筒壳过渡的屈曲分析 (GMNIA) 案例。通过应用所提出的经验公式，观察到与极限强度的良好相关性。已经提出了一个基于几个案例研究的简单经验解决方案，可以合理地用于估计几何和材料非线性分析 (GMNA) 和几何和材料非线性缺陷分析下的外部加压锥筒壳过渡的屈曲（ GMNIA) 案件。通过应用所提出的经验公式，观察到与极限强度的良好相关性。已经提出了一个基于几个案例研究的简单经验解决方案，可以合理地用于估计几何和材料非线性分析 (GMNA) 和几何和材料非线性缺陷分析下的外部加压锥筒壳过渡的屈曲（ GMNIA) 案件。通过应用所提出的经验公式，观察到与极限强度的良好相关性。