LNG泄漏气体浓度和温度扩散过程计算  

Gas concentration and temperature diffusion numerical simulation for LNG leakage

作　　者：陶婧莹 李兆慈[1] 郭志超 张娜 Tao Jingying;Li Zhaoci;Guo Zhichao;Zhang Na(National Engineering Laboratory for Pipeline Safety,Beijing Key Laboratory of Urban Oil and Gas Distribution Technology,China University of Petroleum,Beijing 102249,China;Beijing Tianhai Industry Company Limited,Beijing 101109,China)

机构地区：[1]中国石油大学(北京)油气管道输送安全国家工程实验室•城市油气输配技术北京市重点实验室,北京102249 [2]北京天海工业有限公司,北京101109

出　　处：《低温与超导》2020年第6期12-19,25,共9页Cryogenics and Superconductivity

基　　金：国家重点研发计划(2017YFC0805804)资助。

摘　　要：利用高斯烟羽模型进行LNG泄漏过程模拟,得到LNG泄漏后扩散浓度场和温度场分布。参考天然气燃烧下限0.0358 kg/m^3与低温温度规定291 K确定了气体浓度场和温度场的危险区域范围,分析了环境风速和大气稳定度参数与泄漏扩散的关系,得出环境参数对浓度场、温度场及危险区域的影响规律:设置参数为泄漏量5 kg/s,泄漏源高度20 m,泄漏孔径50 mm,大气稳定度C级,环境风速2、3、4、5 m/s。随着环境风速的增加,泄漏源高度处下风向轴线上最大浓度分别为0.3978、0.2655、0.1992、0.1594 kg/m^3,最低温度分别为153.9、168.3、180.1、189.9 K,浓度场和温度场沿下风向和横风向扩散加剧,危险区域减小;设置环境风速2 m/s,大气稳定度A、B、D、E级,随着大气稳定度的增加,泄漏源高度处下风向轴线上最大浓度分别为0.2124、0.2544、0.2615、0.3913 kg/m^3,最低温度分别为177.4、170、169、154.3 K,浓度场和温度场沿下风向和横风向扩散减缓,危险区域增加。Gauss plume model was used to simulate the LNG leakage process,and the natural gas concentration field and temperature distribution were calculated.According to the combustion lower limit of natural gas with 0.0358 kg/m^3 and low temperature regulation at 291 K,the hazardous areas of gas concentration and temperature fields were determined.The effects of ambient wind speed and atmospheric stability parameters on leakage diffusion were analyzed,and the relationship among ambient parameters and gas concentration field and temperature field were obtained.As the ambient wind velocity increased,the maximum concentrations on the downwind axis at the leak source height respectively were 0.3978,0.2655,0.1992,and 0.1594 kg/m^3,and the minimum temperatures were 153.9,168.3,180.1,and 189.9 K,the concentration field and temperature field increased along the downwind and crosswind directions,the hazardous area was reduced.Setting the ambient wind speed to 2 m/s and atmospheric stability to A,B,D and E,as the atmospheric stability increased,the maximum concentration on the downwind axis at the leak source height respectively were 0.2124,0.2544,0.2615,and 0.3913 kg/m^3,and the minimum temperature respectively were 177.4,170,169,and 154.3 K,the concentration field and temperature field decreased along the downwind and crosswind directions,the hazardous area was increased.

关 键 词：液化天然气 泄漏 扩散 数值模拟 

分 类 号：TE821[石油与天然气工程—油气储运工程]