Experimental and Modeling Study on Char Combustion
Experimental and Modeling Study on Char Combustion
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DOI：
10.1021/ef900018b
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发表时间：
2009-04
期刊：
影响因子：
5.3
通讯作者：
Juan Yu;Mingchuan Zhang
中科院分区：
文献类型：
--
作者：
Juan Yu;Mingchuan Zhang
在FTIR在线测量系统实验验证的基础上，首次将严格的连续膜模型理论计算结果与目前仍广泛应用于煤粉火焰数学模型的简单单膜模型理论计算结果进行了比较。结果表明，单膜模型对着火温度和着火后燃烧的预测存在较大的误差，在实际应用中应受到一定的限制。在此基础上，提出了一个考虑有限速率多相还原和氧化反应影响的改进焦炭燃烧模型。该模型给出了总燃烧速率、颗粒表面温度和火焰面处气体温度的显式代数表达式。与单膜模型相比，本模型的预测结果与连续膜模型的预测结果和实验数据吻合得更好。该模型也比连续膜模型更容易集成到工业煤粉火焰的综合计算程序中。参考文献21篇，14图。
In this study, on the basis of experimental verifications with an FTIR online measurement system, theoretical calculations by using the strict continuous-film model were first compared with those by the simple single-film model that is still widely used in mathematical modeling of pulverized coal flames. The results indicated that the single-film model has some significant errors in its predictions of the ignition temperature and the combustion following ignition and hence should have some restrictions on its application. Then an improved char combustion model has been presented, taking into consideration the influence of the finite-rate heterogeneous reduction and oxidation reactions. This model gives the explicit algebraic expressions for the overall rate of combustion, the surface temperature of the particle, and the gas temperature at the flame sheet. Compared with the single-film model, predictions by the present model were in much better agreement with those predicted by the continuous-film model and the experimental data. The novel model is also much easier to be integrated into the comprehensive computing codes for industrial pulverized coal flame than the continuous-film model. 21 refs., 14 figs.