薄壳结构内气体爆炸破坏后果数值模拟研究

摘要

In order to study gas explosion destructive effect,an equivalent model of high pressure gas with its main parameters determined by calculation was proposed according to the key characteristics of accidnet data,obtained in accident analysis.By using Shell /Euler coupling algorithm of AUTODYN,a numerical simulation for methane destructive effect was performed.According to the simulation results of one dimethylbenzene explosion accident,it is shown that the dimethylbenzene explosion can cause a certain degree of structural damage to the box-type beam.The welding joints between the roof and sides of the beam were partially ruptured while the welding joints between the side and floor were completely broken.High-pressure products rush out of the floor.The simulation results agree well with the accident destruction features and the simulation method was thus verified.Evidently,the simulation can directly describe the dynamic evolution process of explosion.Besides,the high pressure gas model proposed can reliably consider gas properties,and accurately work out gas type,content and filling position.The analysis results also indicate inner ribs can strengthen the shell of the box-type beam.By the analysis,the explosion risk of dimethylbenzene was expounded,so the results may promote the norm-setting for places involving dimethylbenzene,and provide references to similar safety design.%为研究气体爆炸对结构的破坏效应，依据分析得出的事故数据，计算高压气体主要参数得出高压气团模型，采用 AUTODYN，设置合理的流出边界及联接强度，建立 Shell／Euler 耦合模型，模拟了二甲苯气体爆炸效应。结果较好地描述了结构内爆炸演化过程，二甲苯爆炸导致箱式梁产生一定程度的结构破坏，箱式梁顶板与侧板的焊接点部分断裂，底板与侧板联接失效。仿真结果与事故特征基本吻合，验证了所用模拟方法的有效性。提出的高压气团模拟法基于气体性质，分析爆炸事故特征，确定爆源气体种类并定量其体积及分布。分析仿真结果发现内部加强筋可强化箱式梁。该研究进一步确定二甲苯的燃爆危险性，为二甲苯使用场所提供安全依据及设计参考。