Study On Fire Smoke Control Effect Simulation Of Underground Store

Underground construction has its particularity, is surrounded by soil or rock, only the internal space, no external space, the heat loss is not easy. Few exit connected with the outside, hard to use natural ventilation and lighting, rely on artificial lighting and mechanical ventilation. Sense of direction is poor inside, if the structure is slightly more complex, it is not easy to find the nearest exit quickly. Compared with the general underground construction, underground shopping store is of its own characteristics, generally located in the downtown area, large area, more people inside, rich materials, and many of the materials are combustible or flammable. Because of these characteristics, while the underground shopping store is on fire, higher temperature and more smoke inside, hard to evacuate, Fighting difficult.With very few exceptions, there is a lot of smoke on fire. Fire smoke is a mixture consisting mainly of the air entrained in, as well as water, carbon dioxide, other products of incomplete combustion, pyrolysis product, and carbon monoxide, other toxic or hazardous substances, solid particles, liquid droplets and so on. The presence of fire smoke can reduce visibility of the space, high temperature flue gas will make the fire spread rapidly and cause harm to people directly. According to fire statistic, a large part of the fire victims died directly or indirectly from fire smoke harm, so the research of fire smoke control plays an important role in ensuring the safety of the people in underground buildings.For the existing smoke control system of an underground shopping store, select FDS as fire simulation software based on compartment fire and smoke theories, and build the geometric model, study to set growth curve of heat release rate and the maximum heat release rate and determine the boundary conditions and simulation parameters to simulate the assessment. According to the selected risk criterion, analyze simulation results and suggest improvements for the problems identified, then do the simulation again to verify the improvements. The results show significant improvement by optimizing the existing smoke control, in addition, one more evacuation outlet will greatly shorten the evacuation time and can increase the amount of wind natural complement, can better improve the effect of smoke control.