Subway Station Fire Gases Of Space-time Model And Simulation Research

With the acceleration of urbanization in China,urban traffic problems are becoming more and more serious.Subway,as a convenient and fast means of transportation,is favored by many cities.However,the dense personnel,complex internal structure,and vertical and horizontal electrical network of the subway system are very likely to cause fire accidents.In addition,the semi-closed underground space of the subway station leads to a large amount of fire gas accumulation,which seriously damages the health of people and affects the normal evacuation process of the subway station;In the study of subway station fire hazards,there are few studies on the degree of temporal and spatial damage of fire gas,and the theoretical system is relatively weak.Therefore,it is of great theoretical and practical significance for the emergency management of subway station fire to study the time-space model of subway station fire gas invasion and depict the time-space evolution process of subway station fire gas invasion on the basis of fire gas diffusion and in combination with the evacuation rules of personnel.This article considers the time and space change of gas in the subway,the toxic gas diffusion force function of subway stations is analyzed by the theory of fluid mechanics,and the factors affecting gas diffusion are extracted;The subway station fire gas diffusion model is built by combining with the gas diffusion quality-momentum and energy conservation theorem,revealing the subway fire gas space-time distribution rule;Based on the cellular automata model,the migration and evolution rules of personnel in the evacuation process are analyzed to form the evacuation mechanism of subway station.Using Evacuees space location as guidance,the subway station fire gas density at this location point is extracted,based on the static gas abuse model,the space-time distribution of gas concentration is introduced,selecting the appropriate time step,calculating the damage size of gas in the process of evacuation,regarding kill probability as gas evaluation criterion,establishing the time and space model of station fire gas.Taking the GuangGu subway station as an example,a simulation platform was constructed to simulate the process of fire gas attack in the subway station by introducing such factors as the internal environment of the subway station,the attributes of personnel evacuation,the wind flow field changes and the average daily flow of people.Subway station fire simulation results demonstrated the gas diffusion rules,and show the subway fire gas roach on space-time evolution process,the biggest death probability of optical valley subway station platform layer of personnel is 58.7%,the biggest death probability in station hall layer environment is 49.15%,the gas degree curve generate.It further verifies the reliability and practicability of the time-space model of poison gas attack in subway stations.It provides an effective calculation method for quantifying the degree of poison gas attack in subway stations,and provides reliable theoretical and technical support for the emergency management of fire in subway stations.