古商业街木结构建筑防火间距的数值模拟研究

古商业街木结构建筑较多,防火间距先天不足,发生火灾后蔓延迅速,有必要开展木结构建筑引燃特性研究以获得合理的防火间距设置参数.以古商业街为研究对象,以临界温度和热辐射强度作为着火建筑对面木结构建筑被引燃的判定指标,综合考虑环境风速、建筑间距、火源功率、喷淋系统等因素,运用火灾动力学模拟软件FDS分析系列火灾场景下的温度和...

Numerical simulation of the fire separation distance between wooden structure buildings in ancient commercial street

Wooden structure buildings exist in ancient commercial streets, and the fire separation distance is usually inadequate due to the historic layout, which will result in rapid fire spread. It is necessary to study the ignition characteristics of such wooden structure buildings and obtain reasonable control parameters of the fire separation distance. The critical temperature and thermal radiation intensity were taken as the ignition criteria for the opposite wooden structure building across the ancient commercial street. The environmental wind velocity, building distance, fire source power, and sprinkler system were considered. The fire dynamics simulation software FDS were was used to analyze the characteristics of temperature and thermal radiation intensity in various fire scenarios, and the relationship among fire separation distance, fire source power and environmental wind velocity was obtained. The reasonable control parameters of the fire separation distance and relevant fire service requirement are proposed in this paper. While the building distance is less than 3 m, the combination of high-temperature ignition and thermal radiation ignition causes the fire spread. While the building distance is more than 3 m, thermal radiation ignition mainly causes the fire spread. The intensity of thermal radiation near the objective building increases with the environmental wind velocity, and then decreases after reaching the maximum value. There exists the minimum fire separation distance, which is not affected by the environmental wind velocity, minimum fire separation distance is not affected by the environmental wind velocity and is only related to the fire source power. While the fire source power is 3 MW~20 MW, the relationship is linear.