钝体及开缝钝体燃烧器火焰稳定性对比分析

基于回流区中煤粉挥发分释热点燃主气流实现火焰稳定的集总分析模型，导出使煤粉气流火焰稳定的最小口流区长度、最大允许的主气流流速及极限最大可用挥发分释热量的表达式，并以此为准则对钝体及开缝钝体燃烧器的火焰稳定性能进行了对比分析．研究表明，在相同条件下开缝钝体燃烧器有优于钝体的火焰稳定性能．同时在通道流场燃烧器上对几种煤粉进行了两种燃烧器的燃烧性能实验，其结果与理论分析一致．

Flame Stability of Bluff-Body Burner and Slitted Bluff-Body Burner in Pulverized-Coal-Airstream Combustion

Based on the lumped anlytical model for the study of the flame stability resulting from thecombustion of the volatile matter emitted from the pulverized coal in the recirculating zone for preheating and igniting the flame of the coal-airstream, some expressions, the minimum length of recirculating zone, the maximum allowable airflow velocity and the maximum available release heat of volatile,to give a stabilized pulverized-coal-airstream are derived. With these expressions as the criteria, theflame stability of the bluff-body burner and the slitted bluff-body burner is analyzed. The resultsshow that the stability of slitted bluff-body burner is superior to that of the bluff-body burner underthe same conditions. The experiments on combustion performance have been carried out in a ductcombustor with different pulverized-coals being burnt and with bluff-body burner or slitted bluff-bodyburner respectively. The experimental data show that the combustion performance of the slitted bluffbody is better than that of the bluff-body for every pulverized-coal used and these results are conformed to the analytical predictions.