舰船集防区对外通道结构变形及气密性仿真分析

舰船集防区对外通道中，气密门是气密周界上主要的泄漏点之一。目前气密性评估一般采用实验检测的方法。结合有限元仿真方法，在集体防护系统建造前对气密门的气密性进行初步评估。采用设计波法结合国内外军民船规范，利用有限元软件将长期预报得到的设计波波浪动水压力值、重力、惯性力、静水压力等施加到全舰有限元模型上，全面反映真实受载下舰船在设计波下的响应，进而预报全舰变形情况。选择变形较大的密封结构，分析变形条件下密封结构的密封性能。研究结果表明：借鉴全舰结构强度有限元直接计算方法，能有效分析对外通道的局部变形特征；气密门处的局部变形将导致橡胶密封圈接触压力分布不均。结合局部变形的特点，可对密封结构的优化设计提供参考。

Numerical simulation of the deformation and airtightness of the external passageway structure of naval ships' collective protection system

In this paper, an evaluation method for the deformation and airtightness of the external passageway of a ship collective protection system is presented, where the seal structure like doors and windows is selected as the research object. Firstly, long-term prediction of ship's cross-sectional wave-included loads is conducted based on spectral analysis. Next, the parameters of designed waves are determined, and with FEM software MSC/PATRAN, a FEM model of the ship is established. The designed wave pressure is automatically applied to the ship's wet surface elements through PCL language. After obtaining the result of the deformation of the external passageway, a FEM model of sealed structures is built, where the 3D model of deformed doorframe are calculated based on the result of the general ship FEM model. Finally, contact analysis is conducted between sealing strip and the doorframe, and the result under normal contact stress is compared with the given value to evaluate the airtightness of the sealed structure. It can be concluded that the proposed method serves as a good reference to the ship design that has similar requirements.