Numerical simulations of leakage gas dispersion based on soil and atmosphere coupling
WANG Yan1, HUANG Hong1, HUANG Lida1, LI Yuntao2
1. Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China;
2. College of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing 102249, China
Abstract：Most urban gas pipelines are buried underground. Small leaks can occur and are difficult to detect, which is a threat to urban public safety. Thus, gas leaks in buried gas lines need to be detected and assessed. The leaks can be located by analyzing the coupled gas dispersion in the soil and atmosphere. Different governing equations were used to model the dispersion in the soil and atmosphere in OpenFOAM. The flows were coupled through the mass flux leaving the ground surface. The models were used to investigate the impact of the leakage rate on the pressure and concentration distribution and the impact of the convective mass transfer coefficient on the concentration distribution and ground mass flux. The gas distribution in an urban street canyon was analyzed to show that the ground mass flux has little effect on the methane distribution in the street canyon. The model can be used as a reference for leak detection and assessments of buried gas pipelines.
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WANG Yan, HUANG Hong, HUANG Lida, LI Yuntao. Numerical simulations of leakage gas dispersion based on soil and atmosphere coupling. Journal of Tsinghua University(Science and Technology), 2017, 57(3): 274-280.
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2017, Vol. 57 
