寿县合兴钢结构浅谈钢结构厂房火灾特点发布时间：2015-9-7 9:24:24 浏览次数:553
The occurrence and development of fire has dual characteristics of randomness and uncertainty. Randomness is refers to the cause of the fire and is uncertain factors such as time, place, influenced by various factors, follow certain statistics; Certainty that occurred in a particular situation of the fire will spread according to basic certain rule. Combustion process and gas flow process follows the combustion, fluid mechanics and other physical and chemical laws. Fire the certainty of law can be used quantitative engineering research, generally divided into four main stages, namely: at the beginning stage, developing stage, hard phase and phase out.
Steel structure factory building fire risk is mainly manifested in the fire load and fire plume and the factory building geometry size of shape, etc. Ordinary steel structure workshop is the feature of the space is larger, the air is enough, not affiliated to surround close around buildings, some large span large space buildings and even form the air convection, belongs to the early of the fastest growing axisymmetric fire plume. In the early growth stage, the heat accumulating rapidly, higher formation temperature, rising above the fuel of the fire plume. When plume after exposure to the roof of block, and under the ceiling direction at average level of 0.5 m/s speed spread in all directions, forming along the roof surface parallel to the flow of hot smoke layer with thin, after that, the flue gas block and cooling by building palisade, reached a certain thickness and will gradually expand to the internal fire place, form gradually thickening of hot smoke layer, so as to shorten the time of the stepped into the stage of development of violent. Development up to place in front of the fire, the fire between the vortex formation, affect air convection, cause heat accumulation, to achieve full development stage, the temperature of the hot smoke layer and the core temperature.