论文部分内容阅读
针对海底输气管道在服役过程中发生泄漏引发天然气扩散问题,采用计算流体动力学CFD方法,建立海底输气管道泄漏天然气扩散后果预测与评估模型。围绕泄漏天然气在海水中以及从海面溢出后在大气中扩散两种场景,预测天然气在海水中的运移轨迹,评估天然气上浮时间、溢出位置和溢出区域大小等关键风险参数。预测天然气从海面溢出后在大气中的扩散过程,评估天然气在海面形成的危险区域范围,并考虑海面天然气爆燃场景,评估爆燃超压、火灾高温和热辐射等伤害参数的变化规律。研究表明:天然气水下扩散能够引起海面表层海水密度降低,在海面形成的涌流效应,可能对海面浮式结构物的稳定性产生影响;天然气海面扩散风险主要为可燃气云被引燃之后可能发生爆燃事故;CFD模型能够实现对海底输气管道泄漏天然气扩散风险的有效预测和评估,可为海底输气管道泄漏风险管理与应急决策提供参考。
Aiming at the problem of natural gas diffusion caused by the leakage of submarine gas pipeline during service, CFD method was used to establish the prediction and assessment model of the natural gas diffusion effect of submarine gas pipeline leakage. Two scenarios of natural gas leakage in the seawater and its spread in the atmosphere after the leakage of natural gas are predicted to predict the movement of natural gas in seawater and to assess the key risk parameters such as natural gas floating time, overflow location and the size of overflow area. Predict the diffusion of natural gas in the atmosphere after it overflows from the sea surface, assess the range of natural gas formed in the sea surface, consider the natural gas explosion scene, and evaluate the variation rules of damage parameters such as explosion overpressure, fire high temperature and heat radiation. The results show that the diffusion of natural gas can cause the density of sea surface water in the sea surface to decrease and the inrush effect on the sea surface may have an impact on the stability of the floating structures on the sea surface. The risk of sea surface diffusion of natural gas mainly occurs after the ignitable combustible gas cloud is ignited Deflagration accident; CFD model can effectively predict and evaluate the natural gas diffusion risk of submarine gas pipeline leakage, which can provide reference for the risk management and emergency decision-making of submarine gas pipeline leakage.