卧罐爆炸初始和二次碎片的特征及对立罐前壁和球罐支柱的危害性

Characteristics of primary and secondary fragments of horizontal tank explosion and their harmfulness to front wall of vertical tank and support of spherical tank

卧罐爆炸产生的碎片具有很强的破坏性,可能导致相邻储罐的破坏,进而引发多米诺效应。因此,研究储罐爆炸产生的初始及二次碎片是非常重要的。将碎片分为爆炸罐体自身和储罐附件在内的初始碎片以及爆炸荷载作用下周边设施破碎所形成的二次碎片,针对初始及二次碎片的数量、质量以及抛射速度建立概率分布模型,利用LS-DYNA软件对初始与二次碎片在不同速度下撞击立罐前壁的过程进行数值模拟研究,最后模拟分析爆炸碎片撞击不同尺寸球罐支柱的过程。结果表明:卧罐爆炸初始碎片数量在统计区间[1,15]内均服从离散指数分布,当碎片的撞击速度较低时,带有长、宽、高的立方体合金钢材料小型罐体碎片的破坏性最大。而当碎片的撞击速度较高时,球体附件碎片贯穿罐壁后罐壁的内能最高,应力分布最广。在本模拟实验中,不同尺寸球罐支柱在小型爆炸碎片撞击作用下均未发生失稳坍塌现象。

The fragments produced by explosion of horizontal tank are destructive,which may lead to the damage of adjacent vessels,and then cause the domino effect.Therefore,it is very important to study the primary and secondary fragments produced by source explosion and target destruction.The fragments were divided into primary fragments including tank bodies and tank accessories,and secondary fragments formed by the surrounding facilities under explosion loads.The probability distribution models of the number,mass and velocity of primary and secondary fragments were established,the dynamic process of the primary and secondary fragments impacting the front wall of the storage tank at different speeds was numerically simulated by LS-DYNA.Finally,the process of fragments impacting the support of spherical tank with different sizes was simulated and analyzed.Results showed that the number of primary fragments obeyed the discrete exponential distribution in the statistical interval of[1,15].Under low impact velocity,the cube alloy steel tank body fragments with length,width and height were the most destructive.When the impact velocity was fast,the internal energy of the tank wall was the highest and the stress distribution was the widest when the accessory fragments completely penetrated into the tank wall.In this simulation experiment,there was no instability and collapse phenomenon of different size spherical tank pillars under the impact of small explosion debris.