水下爆炸载荷作用下浮体模型变形机理研究

Deformation Mechanism of Floating Model Subjected to Underwater Explosion Load

为揭示舰船底板在水下爆炸载荷下的变形机理,设计水面浮体模型,进行实验研究和理论分析.考虑近距离爆炸球面波效应,得到了模型获得的冲击波能量.将聚偏氟乙烯计测得的壁压时程作为浮体模型的输入载荷,并计及模型浮力的变化,得到了模型的最大动能.考虑膜力拉伸应变和弯曲应变的耦合效应,使用拟合的底板挠曲面函数,得到了模型底板的塑性变形能.将模型的动能与塑性变形能之和除以冲击波能与气泡能之和,得到了模型的能量利用率.结果表明:能量利用率随量纲一的数Φ的增加先增加后减小,当Φ在50~90时,浮体模型对水下爆炸能量的利用率达到最高,达到20%~30%.

In order to reveal the deformation mechanism of the ship’s bottom plate subjected to the underwater explosion load, a floating body model was designed, the experimental research and theoretical analysis were carried out. Considering the spherical waves effect of the close-in explosion, the shock waves energy was obtained.The wall pressure time history measured by PVDF was used as the input load of the floating model, and the change of buoyancy on the model was considered, then the maximum kinetic energy of the model was obtained.The coupling effect of the membrane tensile strain and the bending strain is considered, the plastic deformation energy of the bottom plate was obtained by using the fitted bottom plate deflection function. The sum of kinetic energy and plastic deformation energy of the model divided by the sum of shock wave energy and bubble energy,so the energy utilization rate is obtained. The energy utilization rate increases first and then decreases with the increase of the dimensionless number Φ. When the Φ is 50~90, the floating body model has the highest utilization rate of underwater explosion energy, reaching 20%~30%.