中文摘要：

气化炉内火焰声学信号是表征水煤浆气化炉内火焰燃烧及流动特性的重要信息。为了更好地了解气流床气化炉内撞击火焰的燃烧特性及其对气化炉的影响,在多喷嘴对置式气流床气化炉中,进行了两喷嘴撞击火焰和四喷嘴撞击火焰的变工况试验。应用统计理论和Hilbert-Huang变换对炉内火焰声学信号分别进行了时域和频域的分析。结果表明,随着燃料或氧气的增大,火焰化学反应速率加快,燃烧越来越剧烈,火焰的稳定性越来越差,其中氧气对火焰的影响大于燃料。四喷嘴工况的撞击火焰噪声的标准偏差值要大于两喷嘴,但标准偏差随工况的变化小于两喷嘴,说明四喷嘴撞击火焰燃烧剧烈但稳定。低氧燃比工况时,四喷嘴能量和频率的分布主要集中在45Hz以下的低频段和45～100Hz的中频段,比两喷嘴工况更集中于低频段。

英文摘要：

Flame acoustic characterization of a coal water slurry （CWS） gasifier is an important information which can show the flame burning state and its flow characteristics. In order to better understand the burning characteristics of impinging flame and its effect on the gasifier, the four-nozzle impinging flame and two-nozzle impinging flame of the gasifier with different conditions were studied respectively. The statistical theory and Hilbert-Huang transformation were used to analyze the flame acoustic signals in time and frequency domains. The results showed that with the increase of fuel or oxygen, the rate of chemical reaction increased and the flame burned more and more intensely, but the stability of the flame became worse. And oxygen played a key role in the process. The standard deviation of four-nozzle impinging flame noise was greater than that of the two-nozzle impinging flame noise, but the change of the standard deviation was the reverse. It meant that the four-nozzle impinging flame burned intensely but stably. In the condition with a low ratio of CWS feed and oxygen, the noises of four-nozzle impinging flame were concentrated in the low-frequency bands below 45 Hz and the medium-frequency 45--100 Hz band, indicating that four-nozzle impinging flame was more stable.