电磁式涡街流量计测量含气导电液体流量研究  

Study on measuring conducting liquid flow with gas by electromagnetic vortex flowmeter

作　　者：汪春畅 徐科军[1] 许伟[1] 吴建平[1] 梁利平[1] 熊伟 闫小雪 

机构地区：[1]合肥工业大学电气与自动化工程学院

出　　处：《电子测量与仪器学报》2018年第1期174-180,共7页Journal of Electronic Measurement and Instrumentation

摘　　要：在测量含气导电液体流量时,电磁式涡街流量计利用已有的信号处理方法会出现流量信号频率计算错误的现象,造成较大的测量误差。为此,提出基于信号微分和快速傅里叶变换(FFT)频谱分析的算法,放大高频流量信号,抑制低频气泡噪声干扰,使整体流量信号能量占优,从而找到正确的流量信号频率。研制基于DSP的电磁式涡街流量变送器系统。设计一套两相流实验流程,进行气液两相流实验。实验结果表明,当含气量不超过3.9%时,所研制的电磁式涡街流量变送器系统实时测量误差优于±3%,大大减小了测量含气导电液体流量的误差。There are large measurement errors in electromagnetic vortex flowmeter when measuring conductive liquid flow mixed with gas,since the existed signal processing method obtains the wrong flow signal frequency. For this reason,an algorithm based on signal differential and fast Fourier transform( FFT) spectrum analysis is proposed to calculate the correct frequency of the flow signals. It can amplify high frequency signal and suppress interference of low frequency bubble noise,in order to make the energy of flow signals in whole is dominant. An electromagnetic vortex flow transmitter based on DSP is developed,and an experimental process is designed to perform gas-liquid two-phase flow experiments. The testing results show that when gas volume fraction is less than 3. 9%,the measurement errors of the transmitter are smaller than ± 3%,which greatly reduces the conductive liquid flow measurement error.

关 键 词：电磁式涡街流量计 气液两相流 信号微分 FFT频谱分析 流量测量 

分 类 号：TH814[机械工程—仪器科学与技术]