基于等效最小光程的大范围浊度测量方法  

Wide range turbidity measurement method based on equivalent minimum optical path

作　　者：张海韬 王宏远 甄理 郑叶龙[1] 赵美蓉[1] 黄银国[1] ZHANG Haitao;WANG Hongyuan;ZHEN Li;ZHENG Yelong;ZHAO Meirong;HUANG Yinguo(State Key Laboratory of Precision Measurement Technology and Instruments,Tianjin University,Tianjin 3ooo72,China)

机构地区：[1]天津大学精密测试技术与仪器国家重点实验室,天津300072

出　　处：《光学技术》2024年第3期339-345,共7页Optical Technique

摘　　要：浊度测量在水质监测等领域有重要应用。针对大范围浊度测量问题,提出了一种基于等效最小光程的浊度测量方法。利用90°散射法,通过多组光程与散射光强测量值进行线性拟合,计算出光强截距,建立了光强截距与待测浊度的数学关系。该光强截距表征最小光程条件下的等效散射光强,从而减小了高浊度下光程的影响,保证了低浊度和高浊度区间的高测量精度。搭建了13路光程组合的浊度测量实验装置,实验结果表明,在250~2000 NTU的范围内,该方法最大相对误差为2.818%,与散射法直接测量相比,平均相对误差降低约71%,在保证测量精度的前提下扩展了散射法的测量范围。Turbidity measurement has important applications in water quality monitoring and other fields.Aiming at the problem of large-scale turbidity measurement,a turbidity measurement method based on equivalent minimum optical path is proposed.Using the 9o°scattering method,the light intensity intercept is calculated by linear fitting of multiple groups of light paths and scattered light intensity measurements,and the mathematical relationship between the light intensity intercept and the turbidity to be measured is established.The light intensity intercept represents the equivalent scattered light intensity under the condition of minimum optical path,so as to reduce the influence of optical path under high turbidity,and ensure the high measurement accuracy in the low turbidity and high turbidity range.An experimental device for turbidity measurement with 13-path combination was built.The experimental results show that the maximum relative error of this method is 2.818% in the range of 250~2000 NTU.Compared with the direct measurement of scattering method,the average relative error is reduced by about 71%,which expands the measurement range of scattering method on the premise of ensuring the measurement accuracy.

关 键 词：浊度测量 散射法 最小光程 光强截距 

分 类 号：TN29[电子电信—物理电子学]