摘要
为分析和预测天然气泄漏的扩散距离、扩散面积及扩散后的不动火区域,有效控制事故发生及降低事故后果,以某天然气储罐为例,对天然气瞬时泄漏的扩散规律进行了数值仿真。首先,确定适用于轻气的高斯烟团模型;然后,基于高斯烟团模型进行仿真分析,绘制天然气瞬时泄漏扩散的等质量浓度曲线和动火燃爆区域;第三,分析泄漏量、大气稳定度、地表粗糙度等因素对天然气扩散的影响,并分别确定不同条件下的动火燃爆区域;最后,基于数值仿真分析结果,提出天然气泄漏后的应急疏散和救护措施。结果表明:天然气扩散距离和面积随泄漏量增大而增大;大气越稳定,扩散的距离和范围越大;扩散距离随地面粗糙度增大而减小。
The present paper is inclined to introduce our research on the diffusion regularity of the instantaneous leakage of natural gas and its influence so as to provide a safe and reliable guide to the design of the natural gas tank, and to the emergency control measure. It is for the above reasons that this paper not only includes the study of the parameters of the leakage pressure, but also the discussion on the wind direction, the surface roughness and the atmosphere stability. In addition, mention is needed on how to deal with the fire combustion region under operation, the emergency evacuation and the rescue measures after the gas leakage. We have also made a simulation and analysis on how to control and prevent the incidence of the leakage accidents and how to mitigate accident consequences effectively by taking a natural gas tank for the example and forecasting the diffusion distance and area free from the gas leakage. To achieve the above said purpose, we have first of all established a Gauss smoke cloud model for light gas. Secondly, we have drawn the iso-concentration curve and the fire operation combustion area in accordance with our simulated analysis of the said Gauss smoke cloud model in case of the gas instantaneous leakage. Thirdly, we have made an analysis of the influential factors, such as the leakage rate, the atmosphere stability, the ground roughness on the gas diffusion, with the fire operation combustion region in different conditions being divided. And, finally, a detailed discussion has been made on the basis of the simulated results, the emergency evacuation and rescue measures consequently after the gas leakage. Results prove that since the diffusion distance and area increases with the increase of the leakage, the greater the stability of the atmosphere, the greater the diffusion distance and the diffusion range will be, but the diffusion distance tends to decrease with the increase of surface roughness. Thus, it can be seen that what we have found in this paper has made it contribution to the improvement of natural gas tank design as well as the reduction of the frequency of gas leakage accidents so as to make the gas use more reasonable, economical, safe and effective.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2014年第2期51-55,共5页
Journal of Safety and Environment
基金
辽宁省自然科学基金项目(201202022)
大连市科技项目(2011E15SF118)
关键词
安全工程
天然气
瞬时泄漏
高斯烟团模型
扩散规律
扩散距离
仿真分析
safety engineering
natural gas
instantaneous leakage
Gauss smoke cloud model
diffusion rule
diffusion distance
simulation analysis
