FLNG工艺区爆燃冲击强度数值分析及后果评价

CFD数值方法是目前海上浮式设施爆燃冲击研究中得到广泛运用的方法.文中以某FLNG工艺区发生爆燃事件为研究背景,基于通用CFD软件CFX对蒸气云爆炸进行数值分析,提出了基于能量释放方程模拟分析的冲击波安全评价方法,并对能量和能量释放时间两个变量对爆燃冲击强度的敏感性进行研究.该冲击波后果评价方法通过在爆心位置设立以能量大小和能量释放时间为变量的step函数,选定k-ε模型,模拟爆炸冲击获得超压数据,并结合超压伤害准则和TNO爆炸源能量和气云体积的转换关系对冲击波伤害后果进行评价.研究表明:基于CFD的能量释放方程能够很好的模拟爆炸冲击波并获得表征冲击强度的超压数据.方程中变量因素对冲击强度影响显著,特别是爆炸近场区域.提出的安全分析方法可以有效地对爆炸冲击后果进行评价.

Numerical analysis and consequence assessment of detonation shock wave for FLNG process area

CFD numerical analysis is widely applied to the current deflagration research of offshore floating facilities.This paper is based on the deflagration event for FLNG process area and the CFD software（CFX） will be used to simulate gas explosion.A new assessment approach for detonation shock shove is from the simulation analysis based on a energy release equation（＇step＇ function） in CFX and a research on the sensitivity of impact strength from fluctuation in energy and energy release rate also is a important part.This approach exerts a step function in the area of explosion source with model to simulate the shock wave and evaluates the consequence of deflagration with overpressure criteria and the conversion relationship between energy and gas cloud volume by TNO.Based on the consequence of this study,the ＇step function＇ method can effectively simulate blast and obtains accurate overpressure data.Impact strength is sensitive to the two variables,especially for the near-field region.The proposed method can effectively evaluate the consequence of detonation shock wave.