1.College of Automation, Hangzhou Dianzhi University, Hangzhou, Zhejiang 310018, China
2.Department of Automation, Tsinghua University, Beijing 100084, China
3.Henan Institute of Science and Technology, Xinxiang, Henan 453003, China
Abstract：The range of original level measurement methods by acoustic resonance principle is limited by the fundamental resonance frequency (RF). It causes inability in long distance measurement. In order to overcome this limitation, a new liquid level measurement method is presented based on RFs in a special high frequency range. A set of RFs in this frequency range is detected in stead of the fundamental RF. Many measurements can be calculated by the equi-different relationships between adjacent RFs and the RF conversion formula of the level. The mean of these measurements is considered as a final value so as to reduce measuring uncertainty. In addition, the proposed detection algorithm can fast obtain RFs and improve the real-time performance. Experimental results show that new method has longer measurement range, insensitive to some foams or residues. Its measuring accuracy is up to 1‰ better than 3‰~5‰ accuracies of the original methods and the common ultrasonic gauges.
徐晓滨,赵晨萍,夏丙铎,王芝,文成林. 基于固定频段声波共振原理的液位测量方法[J]. 计量学报, 2011, 32(1): 53-57.
XU Xiao-bin,ZHAO Chen-ping,XIA Bing-duo,WANG Zhi,WEN Cheng-lin. A Fluid Level Measurement Method Based on Acoustical Resonance in a Special Frequency Range. Acta Metrologica Sinica, 2011, 32(1): 53-57.
［1］臧怀刚,赵保军,陶然.可测速的智能超声波液位仪［J］.计量学报,2006,27(4):356－359.
［2］朱江.超声波液位仪设计与精确度的研究［D］.吉林:吉林大学,2009.
［3］Donlagic J, Zavrsnik D M. Low-frequency acoustic resonance level gague［J］. Sensors and Actuators, 1996, 57(3):209－215.
［4］Sung Soon Jung, Seung II Cho,Yong Tea kim.Level gauge by using the acoustic resonance frequency［J］.Journal of the korean physical society,2003, 43(5):727－731.
［5］Donlagic J, Zavrsnik D M, Sirotic I. The Use of One-Dimensional Acoustical Gas Resonator for Fluid Level Measurements［J］. IEEE Transactions on Instrumentation and Measurement, 2000, 49(5):1095－1110.
［6］赵辉,丁雷,杨培敏.利用声共振测量关键长度的研究［J］.宇航计测技术,1998,18(6):1－7.
［7］Georgi H.The Physics of Waves［M］.Ptentlce Hall, Englewood Cliffs:NJ,1993,155－171.
［8］Hu Xian-feng. Discussion on the experiment of sound velocity measured by standing wave method ［J］. Physics Experimentation, 2007, 27(1):3－6.
2011, Vol. 32 
