摘要
为预防管道泄漏事故,提高管道运输的安全性,探讨在不同土壤属性和降水条件下,天然气管道在地下小微孔泄漏规律,分析土壤特性和燃气在土壤中的扩散特点及降水对土壤属性参数的影响。建立小孔泄漏量计算模型和三维稳态扩散数学模型,并运用无量纲分析法求解计算方程。通过实例计算分析燃气浓度随埋深的变化情况,燃气浓度和孔径大小的关系,燃气浓度在不同土壤属性下的变化情况,以及燃气扩散到地面达到爆炸极限的时间等。结果表明:泄漏孔径、土壤含水率和土壤种类均是影响扩散规律的重要因素;降水会改变土壤属性,影响燃气在土壤中的扩散速率和范围。
The paper intends to explore the rule of small micropore leakage of buried natural gas pipe- line, especially diffusion regularity of gas in soil under condition of different soil properties and rainfall. Effects of rainfall on both characteristics of soil and characteristics of gas diffusion in soil were analyzed. A model was built for calculating leakage flow of gas. A three-dimensional steady-state diffusion model was built for gas leaking from pipeline. The diffusion equation was solved using dimensionless analysis method. And finally, through example calculations, dependence of gas concentration and parameters including bur- ied depth, aperture size, and soil properties was studied. Besides, the time was calculated for gas concen- tration over the surface to reache the explosion limit. The results show that leakage aperture size, the mois- ture content of soil and soil type are all important factors affecting the rule of diffusion, and that rainfall can change soil properties and affect gas diffusion rate and scope.
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2014年第2期52-58,共7页
China Safety Science Journal
基金
国家自然科学基金资助(50974105)
高等学校博士学科点专项科研基金资助(20105121110003)
关键词
埋地燃气管道
小微孔泄漏
土壤特性
降水
扩散
燃气浓度
buried gas pipeline
small and micro pore leakage
soil properties
rainfall
diffusion
gas concentration
