煤粉燃烧两相流的数值模拟  

Numerical simulation of a pulverized coal combustion two-phase flow

作　　者：张亚平[1] 田玉仙[1] 

机构地区：[1]西安科技大学能源学院

出　　处：《西安科技大学学报》2008年第2期297-300,共4页Journal of Xi’an University of Science and Technology

摘　　要：由于煤粉燃烧受热面区域的气固两相流场测量难度大,为预测煤粉燃烧炉内部流场与两相流浓度场分布规律,以FLUENT为平台,建立了煤粉燃烧炉模型,用PDF来定义燃料成分,气相湍流流动采用标准的k-ε方程模型,气相为无滑移边界条件。颗粒相采用随机轨道模型。利用有限差分法来离散微分方程,对控制方程的求解采用SIMPLE算法。得到了燃烧炉内部温度场,煤液化率的分布规律及煤粉的颗粒轨迹。揭示了挥发分释放与燃烧的过程,剖析了焦炭的燃烧机理,为煤粉在分解炉内的优化燃烧提供了重要的理论参考依据。模拟结果有助于煤粉炉改造和节能。It is difficult to measure gas-particle two-phase flow for a pulverized coal combustion. In order to predict the flow field and mixture fraction distribution, a model of a simplied pulverized coal combustion stove with FLUENT procedure was set up. The fuel composition was defined in PDF. Standard k-ε and no-slip boundary condition was used for the gas phase turbulence. Coal particles phase makes use of stochastic tracking model, finite difference method and SIMPLE arithmetic was utilized to discrete and solve a reacting equation. Mean mixture fraction distribution, devolatilization rate, and char burnout rate was obtained, as well as the trajectories of individual particles was displayed. It was showed that ration of solid-gas regulation can enhance combustion rate and reduce pollution, which is conducive to reconstructing of the pulverized coal stove and save energy.

关 键 词：煤粉燃烧 两相流 数值模拟 

分 类 号：TQ534[化学工程—煤化学工程]