基于管道爆炸数值模拟的架空天然气管道并行间距研究

Safe distance of overhead parallel pipeline calculated by numerical simulation of gas pipeline explosion

关键词:  并行管道  TNT当量法  管道爆炸  并行间距

Key words:  parallel pipeline  TNT equivalent method  pipeline explosion  parallel spacing

摘要:

从天然气管道失效泄漏引发爆炸现象出发,通过理论分析建立架空管道泄露模型,应用Matlab计算出管道泄露总量中参与爆炸的体积,通过TNT当量法将体积值转化为管道爆炸模型的初始当量。利用Autodyn软件建立管道爆炸物理模型,计算不同并行间距下管道受并行管线爆炸冲击超压及变形量。依据管道椭圆应变准则评定不同并行间距下管道受冲击变形风险。结果表明:架空管线受并行天然气管线爆炸冲击产生的变形破坏为超压破坏和冲量破坏两种形式。架空管道大变形位置为正对爆炸源最近点和背对爆炸源最远点。架空天然气管道安全并行间距:一级和二级风险距离分别为0～2和2～5m,三级风险距离为5m以上。将数值模拟结果与理论计算结果对比,验证了该数值计算方法的可行性。

Abstract:

Based on the explosion phenomenon caused by natural gas pipeline failure, leakage model of overhead pipeline was established by theoretical analysis method. The volume of gas participating in the blast was calculated by Matlab software, and the initial volume values of pipe explosion model couod be converted to equivalent by TNT equivalent method. In addition, pipe explosion physical model was established by Autodyn software, and the explosion overpressure and deformation impacted on the parallel pipeline were calculated over different parallel pipeline spacing. According to the pipe ellipse strain criterion, the impact deformation risk was assessed over different parallel pipeline spacing.The results show that the deformation failures of overhead lines are the overpressure and impulse damage failures in two forms. The deformation position of overhead pipeline is the nearest point facing explosive source and the farthest point back to explosive source. The safe overhead parallel spacings are obtained. The spacing less than 2m is the first risk distance, the secondary risk distance is spacing from 2m to 5m, and the third risk distance is spacing more than 5m. The comparison between the numerical simulation results and the theoretical calculation results verifies the feasibility of the numerical method.