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本文从燃料预热角度出发，建立了一个无风状态下火焰沿层状疏松燃料水平定常蔓延的物理模型。在该模型中，假设环境无风，从热学角度考虑燃料很薄。燃料加热机制包括火焰辐射，燃料中的热辐射和热传导以及火焰通过扩散对流对其附近燃料的加热，散热机制包括燃料上表面辐射散热和对流散热。计算得到了火焰蔓延速度同几个主要影响因素之间的关系，并用曲线拟合技术得到了一个简单的函数表达式。该模型用实验进行了检验，由于对燃料中的热辐射采用了辐射向量的处理方法，同时，考虑了火焰卷吸引起的强迫对流对散热的影响，从而伎计算结果同实验取得了较好的一致。
In this paper, from the perspective of fuel preheating, a physical model of the steady spread of flame along stratified loose fuel under no-wind condition is established. In this model, assuming that there is no wind in the environment, the fuel is very thin from a thermal viewpoint. The fuel heating mechanism includes flame radiation, heat radiation and heat conduction in the fuel, and heating of the fuel near the flame by diffusion convection. The heat dissipation mechanism includes radiation heat and convection heat dissipation on the upper surface of the fuel. The relationship between the flame spread rate and several main influencing factors was calculated and a simple function expression was obtained by curve fitting technique. The model was tested experimentally. Because of the radiation vector treatment method for heat radiation in fuel, the influence of forced convection on heat dissipation caused by flame entrainment was taken into account. Therefore, the calculation result is better than the experiment Consistent.