The Numerical Models Research On Mine Fire Smoke Flow And Regularities Of Temperature Distribution

Mine fire not only destroyed the equipment and burned up so many coal resources, but also produced a lot of smoke pollution in the event of fire spreading which will lead to the wind speed temperature goes up quickly in the whole mine ventilation, even in some roadway lead to the windburn, appear the smoke flow inverse retreat phenomenon that cause wind speed reflux and disorder, expand the affected area, increase the fire damage. If mine fire prevention measures are inadequate, it may cause a gas explosion leading to more serious damage, high temperature down-hole, toxic environment as a serious threat to the lives and safety of the underground staff. To grasp the mine pressure, temperature and distribution of pollutants quickly and accurately and to take effective measures to reduce the impact of fire as much as possible and to reduce the losses caused by fire, and to guide the evacuation escape correctly, which is has great significance to reduce the risk of a large number of casualties caused by fire and to control the fire development.Experimental study and are two main methods on fire. In contrast, the simulation study has the advantages of less cost, shorter time, repeatable. In recent years numerical simulation study has been widely used with the development of computer technology, CFD (computational fluid dynamics) method for the fire smoke simulation study has outstanding advantages. The CFD software includes FLUENT, PHOENICS, STAR-CD, FDS. The FLUENT can be used for fluids, heat transfer and chemical reaction engineering problems. It has abundant physical models, advanced numerical methods and a strong pre-and post-processing functions, now widely applied to our life.Since the mine fire is a coupling process of underground wind flow, flue gas flow, and the heat of fire, so the simulated key issues include:the air current state of the flow fieldthermal conductivity of temperature field、fire pollutant component distribution of field. To analyze the reasons of the fire combustion characteristics and the wind flow disorders during fire,the mathematical and physical model of typical mine scene of fire burning is built. The application of the FLUENT numerical simulation technology is used in this model, to research the typical mine scene of fire smoke flow and temperature distribution. First, creating a Horizontal single Lane physical model, horizontal face of physical model, by full simplify, using Gambit software to create a physical model when it does not affect the fire simulation. In FLUENT calculation based on RNG k-epsilon turbulence model, the P1radiation model, the energy equation, the component transport model and PDF combustion model,the CO2gas concentration, temperature, radiation range of the roadway distribution and CO2concentration on the horizontal and vertical distribution and sources of ignition point center cross section, according to the FLUENT numerical simulation,it is known that the affection of the inlet velocity to the spread of the fire source, the fuel flow rate to the spread of the fire source, the rules of source of fire burning and the smoke spread characteristics.To control the roadway flue gas recirculation, we can increase the longitudinal ventilation speed, but also accelerate the speed of the spread of the flue gas downstream of the roadway, So vertical wind has an important role to tunnel.fire extinguishing and disaster relief.