涡街流量计的压电探头最优距离和新型测量方法研究  

Research on the Installation Location of the Piezoelectric Probe and the Airflow Velocity Sensing Method of Vortex Flowmeter

作　　者：胡捷 黎波 肖志锋 HU Jie;LI Bo;XIAO Zhifeng(College of Engineering,Jiangxi Agricultural University,Nanchang Jiangxi 330045,China;Jiangxi Engineering Research Center of Animal Husbandry Facility Technology Exploitation,Nanchang Jiangxi 330045,China)

机构地区：[1]江西农业大学工学院,江西南昌330045 [2]江西省畜牧设施技术开发工程研究中心,江西南昌330045

出　　处：《传感技术学报》2021年第10期1346-1353,共8页Chinese Journal of Sensors and Actuators

基　　金：国家自然科学基金项目(31960683);江西省教育厅科技计划项目(GJJ200452)。

摘　　要：针对涡街式流速传感器中电信号微弱并且提取特征涡街信号困难,基于压电方程和湍流N-S方程,建立了流-固-电耦合仿真计算模型,构建了流速测量的新方法。通过理论分析和风洞实验,获得了圆柱绕流体直径(D)、空气流速(v)与压电传感距离(L)以及功率(P)之间的影响规律。仿真计算和实验结果表明:通过提取频域曲线中涡激频率下的功率作为涡街的传感强度,有助于感知微弱的空气流速信号,同时解决噪声等电路上的干扰影响。其次,D增加,最优传感距离(L_(osr))增加;D不变时,功率(Posr)随流速增大而提高,且L_(osr)不变;通过分析得出了采集信号在L_(osr)下最优的本质原因—在该处,涡街成熟且脱落稳定、升力系数(C_(L))稳定。最后,该压电装置测量的最低流速为0.3 m/s。For solving the problem of weak electrical signal and extracting characteristic vortex signal differently in industrial vortex-induced vibration flow sensor,a flow-solid-electric coupling calculation model is established based on piezoelectric and Navier-Stokes equations.Further,the influences of the cylinder’s diameter,the airflow velocities,the piezoelectric sensing distance and the power are obtained according to the finite element method and wind tunnel test.The calculated and experimental results show that the proposed sensor takes advantage of the power in the vortex frequency as the sensing intensity of the characteristic vortex,contributing to successfully sensing weak flow signals.Morever,increasing the diameter of bluff body(D)can linearly enhance the optimum sensing region(L_(osr)),but the region does not change with altering the amplitude of flow velocities.Furthermore,the essential reason for the optimal acquisition signal under L_(osr) is obtained,where the vortex street is mature and stable,and the lift coefficient(C_(L))is stable.In addition,the detection limit of flow rate is 0.3 m/s.

关 键 词：流固电耦合 压电传感器 传感强度 传感距离 

分 类 号：TH11[机械工程—机械设计及理论]