针对气云爆炸的控制室载荷安全系数

Safety coefficient of control room load based on gas cloud explosion

对控制室爆炸载荷的研究主要包括建筑设计载荷与概率爆炸载荷两个方面,并未充分考虑输入参数与计算模型的不确定度对输出结果的影响,采用GDS系统对气云进行探测时,难以保证设计指标的保守性。基于不确定度理论,通过分析气体泄漏扩散以及气云爆炸过程,提出控制室等受体爆炸载荷的安全系数计算分析方法。选取对爆炸后果影响较大的输入参数,利用拉丁超立方抽样法确定输入样本,基于高斯扩散理论提出等价云体积计算模型,通过多能法的应用得到气云爆炸的冲击波超压作为输出,分别利用蒙特卡洛方法与Sobol指数法计算其不确定度与参数敏感度,进而得到安全系数。结果表明:应用于某LNG罐区,依据实际工况选取不确定性参数及其取值区间后,可定量得到泄漏场景下的安全系数;考虑安全系数后,可增强受体爆炸载荷分析的保守性,有效提高对事故的防控能力,并为GDS系统探测提供依据。

The research on the explosion load of the control room mainly includes two aspects,which are the architectural design load and the probabilistic explosion load. But the effect of uncertainty of the input parameters and calculation model on the output results has not been fully considered. It is difficult to ensure the conservativeness of the design index when detecting the gas cloud by using the GDS system. So the calculation and analysis method of safety coefficient was proposed, aiming at the explosion load of control room and other equipment under control(EUC) based on the uncertainty theory, by analyzing the process of gas leakage dispersion and gas cloud explosion. The input parameters with significant impacts on the explosion consequence have been selected, and the Latin hypercube sampling was used to determine the input samples. The calculation model of equivalent cloud size was proposed based on the Gaussian diffusion theory.The shock wave overpressure was used as the output in the light of the application of the multi-energy method. The Monte Carlo method and Sobol index method were used to calculate the uncertainty and parameter sensitivity respectively, and then the safety coefficient was obtained. The results show that applying the methodology to a LNG tank area, the uncertainty parameter can be selected and their interval can be determined according to the actual working conditions. Comparing by scatter plot of explosion overpressure and input parameters,the safety coefficient can be quantitatively obtained in different leakage scenarios. Data analysis shows that the safety coefficient can enhance the conservation of EUC s explosive load. In addition, it can improve the ability to prevent and control accidents, and provide the basis for GDS system detection.