存在可变残留层的固体可燃材料热解数值模型

Numerical Model of the Pyrolysis of Combustible Materials with Volatile Residual Layer

采用偏微分数值模型,使用热解界面预估循环迭代的方法,对存在可变残留层材料的热解过程进行了详细研究.将数值结果同准确解以及积分模型结果进行了比较,模拟并分析了材料残留率对材料热解速率的影响.结果表明,积分模型中温度分布采用二次三项式假设在热解发生初期将带来很大误差,热解速率结果高于微分模型结果.并且残碳率的高低对热解速率及相应的外表面温度变化有很大的影响.模型过程具有相当高的准确性和可靠性.

The paper does an in-depth research on the numerical model of pyrolysis process of the materials with volatile residual layer by using pre-evaluation iteration method. Besides, a comparison is made between numerical simulation results and those of precise solution and integral model. And the simulation and analysis of effect of residual ration on pyrolysis were at last made. It is shown that the mass loss rate of integral model assuming quadratic polynomial temperature distribution is higher than that of the differential model because of its error caused in the initial time of pyrolysis. And the residual ration have great influence on the variation of the mass loss rate and the external surface temperature, the simulation is accurate and reliable.