基于Mie散射理论及热力学原理，分析颗粒物粒径检测过程中粒径通道的穿越现象，揭示了白色光源下颗粒物物性对在线检测结果的影响机制及规律. 结果表明，颗粒的吸收性会引起检测粒径发生穿越现象，粒径穿越通道数与颗粒粒径和折射率的实部与虚部密切相关. 2种吸收性颗粒(A和B)粒径的在线检测值远小于真实值，且粒径跨越了多个通道. 对粒径检测值进行修正，颗粒A和B的中位粒径分别由0.751和1.657 μm变成1.668和2.759 μm，与SEM测量结果(1.604和2.685 μm)的误差均在5%内，验证了颗粒在线检测理论及分析方法的合理性和结果的准确性，同时表明颗粒吸收性对检测结果有较大影响.
Impact of physical properties of particles irradiated by white light on online measurement was explored. The shifting phenomenon of measured particle channels was analyzed based on the Mie scattering theory and thermodynamic principles. The results showed that the particle absorptivity affects the shifting of particle channels, the number of which relies greatly on the particle diameter as well as both the real and imaginary parts of refractive index. The online measurement of the diameters of two absorbing particles (A and B) reveals that the measured values (0.751 and 1.657 μm, respectively) are far smaller than their real counterparts, thus requiring further correction to the preliminary data based on the foregoing theories. Besides, particles of both types strode over multiple particle channels. The newly-corrected diameters of particle A and B transformed to be 1.668 and 2.759 μm, respectively, with an acceptable deviation of 5% as compared to the SEM result of 1.604 and 2.685 μm, which validates the rationality of the theoretical methods adopted here and further corroborates our results.
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