摘要
基于大涡模拟(LES)技术,对不同风速下的火旋风进行数值模拟。运用最小二乘拟合方法研究不同风速下火旋风的中心漂移角速度的变化,其结果表明:随着风速的增加,中心漂移角速度的变化规律遵循某3次方多项式变化趋势,发现存在某一临界风速(3.18m/s)对火旋风中心漂移角速度的变化速率有较大影响。同时,对热量释放率及火焰温度场进行分析,认为随风速的增加,热量释放率逐渐增加且波动逐渐减小,火焰温度场分布梯度逐渐增加,高温区分布呈现连续纺锤面分布形式。
The large eddy simulation（LES） technology was used to simulate the fire whirl under different wind speed. The center shift angular velocity of fire whiff was studied with the method of the least square fitting, the results show that the changing law of the center shift angular velocity follows the trend of a cube polynomial. There is a critical wind velocity （3.18 m/s）, which has big effect on the changing rate of the center shift angular velocity. At the same time, analysis on the heat release rate and the temperature field shows that, with the increasing of the wind speed, the heat release rate and the distributing gradient of the temperature field increases gradually, yet the fluctuation of the release decreases gradually, the temperature distribution in high temperature area takes on a continuous spindle surface.
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2009年第9期78-82,共5页
China Safety Science Journal
关键词
不同风速
火旋风
中心漂移角速度
临界速度
热量释放率
温度场
different wind
fire whirl
center shift angular velocity
critical wind velocity
heat release rate
temperature field
