火灾中烟气羽流的混沌行为  

Study on Chaotic Behavior of Smoke's Plume in Fire

作　　者：卢苇[1] 马晓茜[1] 张凌[1] 余晓福 

机构地区：[1]华南理工大学电力学院,广州510640

出　　处：《燃烧科学与技术》2002年第3期220-223,共4页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目 (30 0 70 62 9)

摘　　要：由浮力射流的一般方程导出描述火灾中烟气羽流的偏微分方程 ,基于不确定论的观点 ,遵循洛仑兹的研究方法 ,发现可用 L orenz方程来研究烟气羽流。通过研究 L orenz模型 ,讨论了 Prandtl数变化时 ,方程解的性质。基于此 ,用 L orenz模型研究烟气羽流的混沌行为 ,发现在 Pr=0 .7,b=0 .0 1,145 0 <r<2 10 0时 ,可能获得混沌解 ,但与初值密切相关。烟气羽流出现混沌 ,表明流态由平稳对流向不稳定对流转变 ,此时可能产生火旋风 ,使灾情扩大。联系火灾实际过程与产生混沌解时的参数 。The partial differential equation describing smoke's plume in fire is deduced from the general equation describing buoyant jet.On the basis of non-deterministic view,the writers find that the smoke plume can be studied by Lorenz equation following the method used by Lorenz.Studying Lorenz model once again,the writers discuss the solution's behavior of Lorenz equation when the Prandtl number changes.Basing on this research,the writers use Lorenz model to study the chaotic behavior of smoke plume,and discover at Pr=0.7,b=0.01 and 1 450<r<2 100 the equation likely gets chaotic solution which is closely correlated with initial values.If chaos appears in smoke plume,it shows that the flow state changes from the stable convection to non-stable convection.In this condition,fire whirlwind maybe takes place so as to spread the disaster.Considering the practical process of fire and the parameters of chaotic solution comprehensively,the writers raise an idea to predict and control fire.

关 键 词：火灾 烟气羽流 混沌 

分 类 号：TQ038.7[化学工程]