外界风对小城镇多层建筑火灾流场的影响

随着市场经济的不断发展,城市化的进程加快,农村人口向城市流动,使小城镇建设规模不断扩大,因而火灾等各种灾害对小城镇居民的生命和财产所造成的损失也越来越大。火灾时,外界风向、风速对火灾流场可能产生很大的影响。笔者根据小城镇一般民宅和建筑物的高度特点建立相应的几何模型和物理模型,利用Phoenics软件,从理论上研究了小城镇一幢楼房不同位置的房间发生火灾时,外界吹来不同风速的正向或侧向风,对房间内外稳态温度场与流场的影响。特别研究了房间内热气流流出窗外向上运动的浮力和外界风力相互作用发生的现象及其对房间内流动的影响。同时,还对不同外界风速情况下,房间内外速度中性面倾斜的角度等问题进行了初步讨论

Influence of Wind on the Fire Flow Field of Multi-storey in Small Town

Urbanization quickens as the market economy develops. The scale of town construction expands while the threats from disasters such as fire on people's lives and properties are increasing. During the fire, the direction and speed of the external wind may exert great influence on airflow field of the fire. The corresponding geometry model and physical model in height characteristic of the buildings of the general civilian residences are set up. Using Phoenics software, the effects of wind with different velocities and directions blowing towards and along a 4-storey building are studied. The airflow field and temperature contours induced by a fire placed at different positions are examined. The interactions of buoyancy of the hot gas with the wind inside and outside the building are also studied. The declining angle of the velocity neutral planes inside and outside the building is investigated.