水工物理模型水下高精度超声水位测量  

Underwater high-precision ultrasonic water level measurement method for hydraulic physical model

作　　者：舒岳阶[1,3] 吴俊 周远航[3] 马御风 周世良 SHU Yue-jie;WU Jun;ZHOU Yuan-hang;MA Yu-feng;ZHOU Shi-liang(The Southwestern Research Waterway Engineering Institute, Chongqing Jiaotong University, Chongqing 400016, China;Key Laboratory of Inland Waterway Regulation Engineering Ministry of Transport, Chongqing Jiaotong University, Chongqing 400074, China;Chongqing Xike Waterway Engineering Consulting Center, Chongqing 400016, China)

机构地区：[1]重庆交通大学西南水运工程科学研究所,重庆400016 [2]重庆交通大学内河航道整治技术交通行业重点实验室,重庆400074 [3]重庆西科水运工程咨询中心,重庆400016

出　　处：《光学精密工程》2020年第9期2027-2034,共8页Optics and Precision Engineering

基　　金：国家自然科学基金青年基金资助项目(No.51508059);重庆市基础研究与前沿探索项目资助(No.cstc2018jcyjAX0345)。

摘　　要：针对现有水下超声波水位测量方法精度偏低,无法满足水工物理模型实验测量需求的问题,分析了水下超声波水位测量误差来源和误差量级,综合考虑水声速与渡越时间对测量精度的影响,提出了一种水下高精度超声水位测量方法。首先,分析了超声波换能器间隙误差对声速测量精度的影响,提出了间隙误差计算方法,从原理上消除了水体环境变化对水位测量精度的影响;其次,基于超声波回波信号的包络形态不变原则,采用归一化包络时差法检测超声波渡越时间,并给出了离散数值计算算法流程,以减小信号衰减特性的渡越时间检测的影响。理论分析表明,该方法能从水声速和渡越时间两方面同时减小水位测量误差。为了验证本方法的可行性,开发了实验样机,并进行了计量检定实验,实验结果表明,在400 mm量程范围内,水位测量误差小于0.1 mm,满足水工物理模型实验高精度水位测量需求。Existing underwater ultrasonic water-level measurement methods have low accuracy and cannot meet the needs of hydraulic physical model experimental measurements.To solve this problem,herein,the source and magnitude of the error are analyzed.By considering the effect of water sound velocity and transit time on measurement accuracy,an underwater high-precision ultrasonic water-level measurement method is proposed.First,by considering the effect of the gap error of the ultrasonic transducer on the accuracy of sound speed measurement,a gap error calculation method is proposed,and the effect of changes in the water environment on the accuracy of water-level measurement is eliminated in principle.Second,according to the principle of the constant shape of the ultrasonic echo signal,the normalized envelope time difference method is used to detect the ultrasonic transit time,and a discrete numerical calculation algorithm flow is designed to reduce the impact of transit time detection of the signal attenuation characteristics.A theoretical analysis shows that the method can reduce the measurement error of the water level in terms of sound velocity and transit time.To verify the feasibility of the proposed method,an experimental prototype was developed,and a metrological verification experiment was carried out.The experimental results demonstrate that the error is<0.1 mm in the 400 mm range,showing that the proposed method can be widely used in high-precision water-level measurement in hydraulic physical model experiments.

关 键 词：水工物理模型 高精度 超声 水位 间隙误差 包络检测 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] TH691.9[自动化与计算机技术—计算机科学与技术]