受辐射加热的煤粉颗粒群着火模型

Ignition Model of Pulverized-Coal Cloud Heated by Radiation

本文建立了仅受辐射加热的煤粉颗粒群着火的不稳态模型。通过数值模拟，研究了煤粉浓度与颗粒群的着火方式、着火时间和着火温度等的关系。研究表明，颗粒群着火时间与煤粉浓度的倒数成线性关系；当煤粉浓度由高向低变化时，颗粒群的着火方式会由均相着火向多相着火过渡，其临界浓度随辐射热源的温度、颗粒直径和挥发份含量等的变化而改变。

This paper presents an unsteady-state model on ignition of pulverized-coal cloud heated by radiation. Correlations of coal concentration with the ignition mode, ignition time and ignition temperature of the cloud are predicated by numerical modelling. The results are as follows. Ignrtion time is proportional to the reciprocal of coal concentration. Igniton mode of the cloud transits from homogeneous to heterogeneous when the coal concentration decreases. The critical concentration changes with the temperature of radiation source, particle diameter and volatile content, etc.