中文摘要：

为了研究煤焦颗粒的分形结构对煤焦燃烧特性的影响，采用随机漫步的算法生成了2组具有相近孔隙率和比表面积，但分形维数不同的颗粒模型。从分子运动论的角度建立分形多孔介质中的扩散模型，用简单碰撞理论（simplecollisiontheory，SCT）模拟煤焦与氧气的气固反应。在不同温度下对不同煤焦颗粒模型的燃烧进行了数值模拟，由数值计算的结果得到了不同孔隙结构的煤焦颗粒对应的表观动力学参数。结果表明，煤焦颗粒的分形维数对煤焦的表观反应参数有显著影响，分形维数越大，煤焦表观燃烧反应系数越小，呈现指数关系。

英文摘要：

In order to investigate the effect of the fractal dimensions of the char particles on the combustion characteristics of the coal char, two groups of numerical char particle models with similar porosity and specific surface areas but different fractal dimensions were generated by the random walk algorithm. The diffusion model in the fractal porous media was established based on the kinetic theory of gas molecules. The heterogeneous reaction of the coal char with oxygen was modeled by the simple collision theory （SCT）. The combustions of the char particles with different fractal dimensions were simulated at different temperatures, and the corresponding apparent kinetic parameters were obtained from the simulation results. The results indicate that the fractal dimension of the char particle has a significant impact on the apparent kinetic parameters of the coal char combustion, larger fractal dimensions lead to smaller reaction coefficients, and there is an exponential relationship between them.