光学学报, 2010, 30 (11): 3184, 网络出版: 2010-11-16
基于带通滤波器的透射率起伏信号频谱特征
Characteristics of Transmission Fluctuation Frequency Spectrum with Band-Pass Filters
光学测量 频谱特征 透射率起伏频谱法 带通滤波器 颗粒测量 optical measurement spectral characteristic transmission fluctuation spectrometry (TFS) band-pass filter particle sizing
摘要
透射率起伏频谱测粒技术是根据透射光起伏信号的频谱特征发展起来的一种新的颗粒测量方法, 可用于实时在线测量。研究基于一阶带通滤波器的透射率起伏信号的频谱特征, 重点分析带通滤波器带宽因子对透射率起伏频谱及其反演结果的影响。同时还考虑了无因次光束直径对透射率频谱的影响。结果表明选择较小的带宽因子α有利于提高测量结果的颗粒粒径分辨率, 但是带宽因子α过小会降低透射率起伏频谱的强度从而导致测量产生误差; 反之, 选择较大的带宽因子α有利于获得较强的透射率起伏频谱信号, 但是带宽因子α过大会降低测量结果的颗粒粒径分辨率。
Abstract
The transmission fluctuation spectrometry (TFS) is a new method based on the spectral characteristics of the transmission fluctuation spectra, which is developed recently for real-time, online/inline particle analysis in two-phase flow. Both the particle size distribution and concentration can be measured simultaneously. The characteristics of the transmission fluctuation spectra with the 1 st order band-pass filters is presented detailedly. The effects of the filter band width parameter on the spectrum and on the inversion results are analyzed together with the effects of the dimensionless beam diameter (beam-to-particle diameter ratio). Numerical calculation and experiments show that a small value of band width parameter can improve the resolution of measurements but reduce the strength of the spectrum and hence bring errors into the results. On the contrary, a big value of band width parameter is beneficial to obtain a strong spectrum but lead to low resolution of measurement.
许亚敏, 沈建琪, 蔡小舒. 基于带通滤波器的透射率起伏信号频谱特征[J]. 光学学报, 2010, 30(11): 3184. Xu Yamin, Shen Jianqi, Cai Xiaoshu. Characteristics of Transmission Fluctuation Frequency Spectrum with Band-Pass Filters[J]. Acta Optica Sinica, 2010, 30(11): 3184.