摘要
对高温复杂介质微纳米尺度含碳固体颗粒成分进行快速检测研究。以高纯氢气火焰中淮南烟煤未完全燃烧为例,采用高能脉冲激光束照射火焰中的碳粒子,提出多段式指数函数拟合不同尺度受热粒子激光诱导辐射光谱时域混合信号的方法,同时结合Kn数判断受热粒子所处的流动区域,确定燃煤氢气火焰中初始碳烟、成熟碳烟以及焦炭或未燃尽煤粒的平均粒径分别为7,25,3×103 nm。并根据不同火焰高度含碳颗粒成分的粒径与相对浓度变化,探索煤粉燃烧过程中微纳米尺度碳粒组分的演变特性。为高温复杂介质中超细颗粒物尺寸分布提供了一种快速、有效的检测手段。
A rapid measurement of micro-nano carbon particles within complicate combustion media is investigated. Carbon particles from pulverized coal combustion in the pure hydrogen flame are heated by a high-power pulsed laser beam. The size distribution of carbon particles is obtained using a multistage exponential function method to fit time- resolved radiation emitted by the laser-heated particles, where the flow zone is determined by Kn. The results show that three sizes of carbon particles exist and the average diameters are 7 nm, 25 nm, 3μm, respectively, which correspond to the newly-born soot, mature soot, and char or unburned coal particles. The variations of each kind of carbon particles during coal combustion are investigated according to the size and relative concentration of each particles component versus the flame height. The above method can be used as a tool for rapid detecting size distribution of multi-scale carbon particulates under the high-temperature environment.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2013年第4期173-178,共6页
Chinese Journal of Lasers
基金
国家自然科学基金(51206144)
浙江省自然科学基金(LY12E06003)资助课题
关键词
信号处理
粒径
激光诱导辐射
多段式指数函数
煤粉
氢气火焰
signal processing
particle diameter
laser-induced radiation
multistage exponential function
pulverized coal
hydrogen flame
