中文摘要：

建立了球坐标系下考虑煤粉挥发分释放、传热、传质和化学反应全耦合的单颗粒热解、燃烧瞬态数值模型，并对陕西神木烟煤的着火、燃烧特性进行分析．结果表明，单颗粒煤粉的着火始于挥发分，且受氧气扩散速率的控制，挥发分火焰能够到达距颗粒中心约29倍颗粒半径的地方．当煤粉热解完成时，炭粒表面生成的CO被引燃，火焰退回炭粒表面附近而使炭粒快速升温，燃烧进入表面氧化反应控制状态．随着燃烧速率进一步提高，炭粒燃烧又开始受到表面还原反应的控制，火焰再次离开炭粒表面．

英文摘要：

The transient whole-coupling model in a spherical coordinate system on single pulverized coal py- rolysis and combustion was developed, taking into consideration various pyrolysis product release, heat transfer, mass transfe/＇, and chemical reactions. The igntion and combustion characteristics of Shenmu bi- tuminous coal were simulated. The result shows that the ignition of pulverized coal begins from volatiles, and the volatile flame can move rapidly to a position departing from the center of the coal particle by about 29 times radius, due to the limitation of oxygen diffusion; when the coal pyrolysis is completed, the CO generated by surface oxidation reaction has been ignited, the flame returns almost to the coke particle sur- face, the particle temperature rises abruptly, and the coke combustion is controlled by the surface oxida- tion reaction; with the combustion rate increasing, the coke combustion begins to be controlled by the sur- face reducing reaction, and the char flame departs from the particle surface again.