基于COMSOL MULTIPHYSICS的高海拔松木阴燃数值模拟

Numerical Simulation of Smouldering Combustion of Pine Wood under High-altitude Conditions Based on COMSOL MULTIPHYSICS

为探究西南高海拔森林地区的松木阴燃特性,该文根据阴燃机理采用COMSOL MULTIPHYSICS多物理场耦合软件建立了松木的一维阴燃模型。模型首先通过文献中常重力条件下的实验数据进行验证,然后通过设定不同林地海拔的压力、环境温度和氧气分压来研究海拔高度对松木阴燃特性的影响。模型结果表明:随着海拔增加,阴燃生成的气体流速明显增加,达到质量损失速率峰值时间延迟;松木阴燃质量损失速率峰值随着海拔高度增加而下降;松木阴燃质量损失速率和炭氧化速率存在相关性。该文提出的数值模型可以预测不同海拔高度下松木的阴燃特性,为预防和控制西南高海拔林区的松木阴燃火灾提供一定的理论依据。

To investigate the smouldering characteristics of pine wood in high-altitude forests in the Southwest region of China,in this study a one-dimensional smoldering model of pine wood was established according to the smoldering mechanism by using COMSOL MULTIPHYSICS.The model was first validated using experimental data under normal gravity condition from literature.Subsequently,the influences of altitude on the smouldering characteristics of pine wood were investigated by setting different pressures and oxygen concentrations corresponding to various altitudes of forest regions.The model results showed that the gas flow velocity in smoldering significantly increased with increasing altitude,and the time to reach the peak decomposition rate was prolonged.This study indicating a substantial correlation between smoldering mass loss and char oxidation rate.The numerical model proposed in this study can predict the smouldering characteristics of pine wood under different altitudes.These findings provide a theoretical basis for preventing and controlling smouldering wildfires in high-altitude pine forests in the Southwest region of China.