水下爆炸船体梁总体响应特性数值模拟

Numerical Simulation on Dynamic Responses of Hull Girder Subjected to Underwater Explosion

为研究水下非接触爆炸作用下船体梁的总体损伤特性,建立了炸药在船体梁中部正下方爆炸模型,应用船体梁总体响应数值计算方法,并结合缩比船体梁模型,试验验证了该方法的有效性,从损伤模式、频率响应等方面研究了船体梁的总体响应特性。结果表明:该数值方法较好地模拟了第一次气泡脉动阶段内梁的响应周期和幅值;在气泡脉动频率接近船体梁一阶湿频率时,随着爆径比减小,船体梁的总体响应模式由鞭状运动逐渐向中垂损伤转变。

In order to study the overall damage characteristics of hull girder subjected to non-contact underwater explosion,a numerical method was established in which an explosive charge was located at the mid-span of the hull girder.The effectiveness of this method was verified by the model test.The damage mode and frequency response were studied to analyze the overall response of the hull girder.Results showed that the numerical method can simulate the response period and amplitude of the hull girder during the first bubble pulsation phase.When the bubble pulsation frequency approximated the first wet frequency of the hull girder,the response mode of girder will transform from whipping motion to sagging with the decrease of the ratio of stand-off to maximum bubble radius.