基于 RKDG 方法的船体板架爆炸冲击响应数值模拟

摘要

In order to simulate the characteristics of far field air explosion shock load,the discretized Euler equations were solved with RKDG method.The numerical model was established and the far field air explosion shock wave load characteristics were simulated.The results were compared with those of the empirical formula.The density and pressure distribution of high pressure shock wave with strong discontinuity were simulated with a Fortran program.Using LS-DYNA,the impulse responses of hull plates under shock load were simulated.The results indicated that the plastic deformation shape profiles appear along the stiffener direction,and the plate grillages reveal local dishing deformation,and the responses are inversely proportional to the distance from the explosion center.%基于欧拉流体力学方程组，对方程组分别进行间断迦辽金法空间离散和龙格库塔法时间离散，采用 RK-DG 方法建立数值模型，模拟自由场空中爆炸冲击波载荷特性，并与经验公式对比，对 RKDG 计算程序进行验证。针对强间断性的空中爆炸冲击波与周围低压空气耦合特性问题，给出了流场密度和压力分布规律。最后编制计算程序，结合大型非线性有限元软件 LS-DYNA，模拟板架结构在空中爆炸载荷作用下的变形和响应特征，计算发现：板架沿着 T 型材出现塑性变形，板格呈现局部隆起的碟形变形区，响应与距离爆心距离成反比。