热辐射下木材的热解与着火特性

在大量的实验基础之上,深入分析了木材热解与着火过程的机理及其中的物理与化学变化,建立了考虑水分蒸发以及表面辐射与对流热损失影响的一维湿木热解与着火微分模型。模型对木材热解与着火过程中的温度变化、失重以及着火时间进行了预测,且预测值与实验值吻合得较好,最后分别将该微分模型、一个经典的热解与着火积分模型的预测值与实验值对比,发现考虑热解与着火过程复杂物理与化学变化的微分模型的预测结果与实验结果吻合较好。

Pyrolysis and Ignition of Wood by Thermal Radiation

Based on the experimental studies of pyrolysis and ignition of wood,a partial differential equations (PDE) model was suggested to study the effect of heat flux on the pyrolysis and ignition of wood with different moisture content.The heat of thermal degradation and effect of evaporation of water were considered in the model.The temperature distribution,mass loss of wood during the process of pyrolysis and ignition were predicted and agreed well with the experimental results.The ignition time of wood pre- dicted by the PDE model was also compared with that predicted by a classic integral model predicting ignition characteristics based on energy balance and ignition criterion.It is found that predictions by the PDE model matched the experimental results better than those by the integral model.