水下非接触爆炸中谱跌效应对设备破坏的影响分析

摘要

弹性安装的舰载设备在受到水下非接触爆炸冲击时产生的谱跌效应会显著降低设备的冲击响应。为研究谱跌效应对舰载设备的设计谱及其设计安装的影响，通过有限元计算对比分析弹簧振子模型的伪速度冲击响应和悬臂梁模型应力冲击响应，同时对比分析上层振子固有频率相同但质量与刚度不同的双层弹簧振子模型的下层振子伪速度冲击响应。发现：谱跌效应发生时，下层设备的伪速度响应和应力响应均有明显的降低，据此须改进舰载设备的三折线伪速度设计谱；增加上层设备的质量和刚度会显著降低下层设备的伪速度响应，并使谱跌效应的频宽范围增加，利用此特性可降低舰载设备中有着特殊固有频率或固有频率集中的零部件的应力响应。%Spectrum dip effect can significantly reduce the shock response of warship equipment with elastic installation under the non-contact underwater explosion environment. In this paper, the finite element method is employed to study the influence of the spectrum dip effect on design spectrum and the installation methods of the warship equipment. The pseudo velocity shock response of the spring oscillator model and the stress shock response of the cantilever model are calculated, compared and analyzed. For the case of the same natural frequency but different mass and stiffness of the top oscillator, the pseudo velocity shock responses of the bottom oscillator of the double spring isolator are analyzed and compared. It is found that the pseudo velocity response and stress response of the bottom equipment significantly decrease when the spectrum dip effect occurs. Then the pseudo velocity of the zigzag design spectrum of the warship equipment needs to be improved; the pseudo velocity response of the bottom equipment decreases and the bandwidth of the spectrum dip effect increases when the mass of the top equipment increases. Some components of the warship equipment with special natural frequency or concentrated natural frequency can be reduced by utilizing the characteristics.