原木燃烧羽流的数值模拟研究

Numerical simulation of plume in log combustion

利用FDS软件模拟原木在0、2m/s风速下的燃烧过程,对原木燃烧粒子运动、火羽流的温度、质量流率、卷吸速度以及热释放速率的规律进行分析。模拟结果表明,轴向温度的变化比较接近于McCaffrey模型;质量流率与高度及风速有密切关系;羽流的轴向卷吸速度有一个随着高度增加而上升的阶段,当达到一定高度后开始下降;热对流和热辐射是热量传递的主要方式。

The FDS software was used to simulated log combus- tion process in wind speed of 0 m/s and 2 m/s, and the log combustion particles movement, fire plume temperature, mass flow rate, entrainment＂ rate and heat release rate were studied. It was showed that the axial temperature change is relatively similar to the McCaffrey model; the mass flow rate is closely related to height and wind velocity; axial entrainment velocity of the plume has a rising stage with the height increasing, and when it reaches a certain height, it begins to fall; heat convec- tion and heat radiation are the main ways of heat transfer.