Dynamic Simulation and Quantitative Risk Assessment of Indoor Heavy Gas Diffusion

Abstract

In order to study the dynamic diffusion process and risk of indoor liquid chlorine leakage, large-scale numerical simulation and risk calculation are carried out based on CFD method. Firstly, a full-scale model in 3km range is established based on CFD calculation, and then the chlorine diffusion process in six leakage scenarios is calculated and analyzed based on pool model. The individual risk and social risk of existing conditions and SIS increase are calculated respectively. The results show that the chlorine will diffuse slowly in the room when the small aperture leaks. In case of leakage of middle hole and larger hole diameter, chlorine gas will quickly fill the warehouse and leak to the outside of the warehouse. The influence of leakage pore size on the diffusion distance of chlorine is very obvious. The total diffusion distance of 900ppm chlorine is 24.2m-401.3m, and the diffusion time is 120s-670s respectively. Under the existing conditions, the individual risk and social risk do not meet the risk acceptance criteria. After sis is increased, the risk meets the acceptance criteria.