激光诱导炽光法定量测量碳烟

Quantitative Measurement of Soot Particle by Laser-Induced Incandescence

利用激光诱导炽光法和高温双色法相结合,得出碳烟体积分数的量化结果;利用碳烟炽光信号衰减速率和炽光物理模型分析得出碳烟粒径的量化结果.分析讨论了LII模型对于不同压力范围内模型的适用性.搭建了LII测试系统,在一台协流部分预混燃烧器上开展了实验,燃料以正庚烷和甲苯作为基础,分别添加乙醇和正丁醇.实验结果显示,含氧燃料的添加有效降低了火焰中碳烟的生成量,同时验证了LII测试系统及定量测试方法的实用性.

This paper describes the application of laser-induced incandescence as a quantitative measurement tech- nique for volume fraction and size of soot particles in the flame. The soot volume fraction distribution was quantified by the two color LII method, while the soot particle size distribution was measured by the time-resolved LII method. LII models with two different sub-models for heat-conduction were compared under the gas pressure of 0.1--3.0 MPa. LII measurement was carried out on a co-flow partial-premixed burner flame with three different fuels. Mixing fuel of n-heptane and toluene was used as a basic case, and oxygenated bio-fuels of ethanol and n-butanol were added, respectively, as comparative cases. The results show that the addition of oxygenated bio-fuel is an effective way to reduce soot emission in the flame, and that n-butanol has a better soot-reduction effect than ethanol.