煤粉颗粒团燃烧过程的数值模拟

煤粉的燃烧在工程实际中很多情况下都是聚团燃烧,颗粒内部传热传质机理复杂。本文根据多孔介质的传热传质学理论,引入对流项,建立了气流场中煤粉团燃烧的三维数学模型,并对不同孔隙率的煤粉团的燃烧过程进行了对比计算,计算结果合理,揭示了孔隙率对煤粉团着火燃烧的影响,为深入研究煤粉团燃烧特性打下基础。

NUMERICAL SIMULATION OF THE COAL CLUSTER COMBUSTION PROCESS

Most of the coal-gas combustion process acting in a dense particle-gas two-phase flow field is coal cluster combustion,which is different from that of a single coal-particle combustion because of the complex inner-cluster heat and mass transfer.In this paper,a 3D mathematical model of a coal cluster combustion in hot air flow,which based on the heat and mass conservation law of porous media,is established.The governing equations include heat transfer equation and gas transfer equation.The detailed heating-up and combustion processes of a coal cluster are obtained and the effects of the porosity are also analysed.All these results are reasonable and offer theoretical bases for futher studying the combustion process of coal-clusters.