运用通用软件MSC.Dytran建立舰船、炸药和水域的有限元模型,并利用该软件进行有限元分析,准确地模拟出了爆炸冲击波在水中的传播过程、空化效应以及整船结构的动态响应,为舰船的抗冲击性能分析提供了输入条件.通过数值模拟可知:炸药水下爆炸后产生的冲击波会以球面波的形式传播开来,速度接近水中声速;冲击波的瞬时压力与时间的关系呈指数分布,但在水面附近由于空化效应迅速衰减,与库尔理论吻合较好.水中爆炸产生的冲击波是影响舰船冲击响应的主要因素,尤其是冲击波的垂向作用影响更大;冲击载荷主要作用集中在舰底,其所承受的应力要比上层建筑大很多,全船的最大应力就集中在船肿的迎爆面位置.水下爆炸产生的冲击波最先作用到舰底,接着冲击振动通过舰船的垂向结构会向上层快速传递,一直传到甲板和上层建筑为止,与此同时垂向结构也会降低冲击振动的强度,所以舰船上层构件所受到的冲击响应会小于舰船底部或舰船舭部,并呈逐步减小的趋势.%In this paper, we construct a finite-element model of ship, explosive and water aera through the common softwares of MSC.Dytran. After that, MSC.Dytran is employed to analyze the finite elements, and accurately simulate propagation process and cavitation effect of shock wave of underwater explosion, as well as the dynamic response of the whole ship structure. These results can serve as the input condition of anti-shock performance anlysis of ship. The numerical simulation shows that: The shock wave of spherical explosive blast propagates in the form of spherical wave, whose speed is close to the underwater velocity of sound; The relationship between instantaneous pressure of shock waves and time is expo-nential, which is in good agreement with Kurt theory, but with a rapid attenuation near the water due to cavitation effect. The vertical function of underwater explosion shock wave is the main factor that influence the shock response of the ship. Fur-thermore, the stress at the bottom of the ship is larger than that of superstructure, as it suffers most of the shock wave load, and the maximum stress concentrates in the midship meeting the blast. Explosion shock wave acts on the bottom of the ship first, and then transfers upwards through the vertical components, until reaching the deck and the superstructure of the ship. Meanwhile, the vertical components can weaken the strength of the shock movement, so the shock response of the upper components of the ship is smaller than that of the bottom or bilge, and decreases gradually .
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