Influence of the soot property uncertainties in temperature and volume-fraction measurements by two-colour pyrometry
Influence of the soot property uncertainties in temperature and volume-fraction measurements by two-colour pyrometry
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DOI：
10.1088/0957-0233/5/12/006
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发表时间：
1994-12
影响因子：
2.4
通讯作者：
S. D. Stasio;P. Massoli
中科院分区：
文献类型：
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作者：
S. D. Stasio;P. Massoli
对双色热分析法计算烟尘温度T和体积分数fv的灵敏度进行了分析。两种不同的燃烧环境的例子高（fv约=10-5）和低（fv约=10-7）烟灰浓度制度。计算考虑了颗粒形状、单色发射率的不同表达式、光学性质的变化、烟灰颗粒的尺寸分布和有限的光探测带宽。结果表明，在选择用于发射测量的（lambda 1, lambda 2）波长和计算T值的算法时，可以采用何种光谱范围，以保证T和fv计算值具有较低的先验不确定性。结果强调了T和fv值对复折射率m=n-ik非常敏感，并且它们不受粒径概率分布的影响。评估了以不同煤烟氢碳比为特征的燃料类型对推断的fv值的临界理论影响。（lambda 1, lambda 2）测量波长高于1.2 μ m的温度值的测定被证明是无效的，在fv约=10-5范围内至少有20 K的不确定度贡献，在fv约=10-7范围内至少有100 K的不确定度贡献。
A sensitivity analysis of the two-colour pyrometry technique for calculation of soot temperature T and volume fraction fv is presented. Two different combustion environments are exemplified for high (fv approximately=10-5) and low (fv approximately=10-7) soot concentration regimes. The calculations are carried out taking into account particle shape, different expressions for monochromatic emissivity, optical property variations, size distribution of soot particles and a finite light-detection bandwidth. The results indicate which spectral range, for the choice of the ( lambda 1, lambda 2) wavelengths employed in the emission measurements, and computing algorithm, for the reckoning of the T values, can be appropriated to guarantee a lower a priori uncertainty in the T and fv calculated values. Results stress the evidence that T and fv values are critically sensitive to the complex refractive index, m=n-ik, and that they are irrelevantly influenced by the probability distribution of particle size. The critical theoretical influence of the type of fuel, characterized by a different soot hydrogen/carbon ratio, upon the inferred fv values is assessed. Determinations of temperature values with ( lambda 1, lambda 2) measurement wavelengths above 1.2 mu m is demonstrated to be invalidated by an uncertainty contribution of at least 20 K in the regime fv approximately=10-5 and 100 K in the regime fv approximately=10-7.