用自相关算法扩展超声涡街流量计的下限  

Extending measured value of ultrasonic vortex flowmeter at lower velocity by using autocorrelation algorithm

作　　者：王萍[1] 万柏坤[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院

出　　处：《天津工业大学学报》2007年第6期39-41,共3页Journal of Tiangong University

基　　金：天津市科技创新专项资金资助项目(06FZZDGX00800)

摘　　要：为了提高超声涡街流量计在低流速下的测量性能,更好地提高信噪比,采用了自相关滤波算法,提出了在调幅式超声涡街流量计中加入自相关滤波算法的设计思路.给出了在高速单片机上应用的具体计算方法、重要参数的取值范围及标准风道上的实验结果.结果表明,该算法在低于0.3 m/s流速时很好地抑制了噪声干扰,提高了信号幅值,较好地解决了低流速测量时数据不稳定的问题,扩展了超声涡街流量计的下限.In order to improve the performance and the signal to noise ratio of ultrasonic vortex flowmeter in lower velocity, the algorithm of autocorrelation filtering is used. On the basis, a correct design thinking of applying autocorrelation filtering algorithm to ultrasonic vortex flowmeter based on amplitude modulation principle is suggested. At the same time, specific computation method in high speed microcontroller, range of important parameter and experiment results in the standard metering pipe are given. The results show that this is a good method which rejects interference noise and restrains destabilization of the measured value at lower velocity（〈 0.3 m/s）and increases the amplitude of signals, and resolves the key problem of the data uncertainty at lower velocity, thus attains the goal of extending the measured value of ultrasonic vortex flowmeter at lower velocity.

关 键 词：自相关 超声涡街流量计 单片机 气体测量 

分 类 号：TP216[自动化与计算机技术—检测技术与自动化装置]