基于电容法的溜管式颗粒物料质量流量计设计与试验  

Design and experiment of a chute mass flowmeter of granular materials based on capacitance method

作　　者：路开新 赵延辉 曹清 雍淦文 王田彬 刘静[1,2] 牛智有 LU Kaixin;ZHAO Yanhui;CAO Qing;YONG Ganwen;WANG Tianbin;LIU Jing;NIU Zhiyou(College of Engineering,Huazhong Agricultural University,Wuhan 430070,China;Ministry of Agriculture and Rural Affairs Key Laboratory of Smart Farming for Agricultural Animals,Wuhan 430070,China)

机构地区：[1]华中农业大学工学院,武汉430070 [2]农业农村部智慧养殖技术重点实验室,武汉430070

出　　处：《华中农业大学学报》2025年第2期94-104,共11页Journal of Huazhong Agricultural University

基　　金：国家重点研发计划项目(2021YFD1300305)。

摘　　要：为实现溜管内颗粒物料质量流量的在线自动测量,根据颗粒物料与空气介电特性的差异,设计了一种基于电容法的溜管式颗粒物料质量流量计。该装置以STM32单片机、电容数字转换芯片AD7746和以MT8816为核心芯片的极板转换电路搭建数据采集系统,实现八极板组合旋转激励传感器电容信号的有效获取。搭建质量流量计试验台架,以玉米、小麦和颗粒配合饲料为试验材料,标定质量流量与累计电容值之间的关系,构建3种颗粒物料的质量流量预测模型,其模型决定系数R2分别为0.990 4、0.993 9、0.987 9。溜管式质量流量计精度验证试验结果显示,在溜管倾角分别为15°、25°、35°、45°、55°,玉米(小麦)质量分别为30、50、70 kg,颗粒配合饲料质量分别为30、50、65 kg时,玉米、小麦和颗粒配合饲料测量的平均相对误差MRE分别为3.11%、3.76%和3.75%。研究结果表明,将电容法应用于溜管输送颗粒物料过程的质量流量在线测量具有可行性,可以实现颗粒物料质量流量的在线自动测量。A chute mass flowmeter of granular materials was designed based on capacitance method and according to the difference in dielectric properties between granular materials and air to achieve online automatic measurement of the mass flow rate of granular materials in the chute.The device was equipped with an STM32 microcontroller,a capacitance-to-digital Converter chip AD7746,and a plate conversion circuit with MT8816 as the core chip to build a data acquisition system,achieving effective acquisition of capacitance of eight-plate rotary excitation sensors.A test bench of mass flowmeter was built.Maize,wheat and granular compound feed were used to calibrate the relationship between the mass flow rate and the value of cumulative capacitance.The models of predicting the mass flow of three kinds of granular materials were constructed,with determination coefficient R2 of 0.990 4,0.993 9,and 0.987 9,respectively.The results of verifying the accuracy of chute mass flowmeter showed that the average relative error(MRE) of measurement accuracy for maize,wheat and granular compound feed was 3.11%,3.76%,and 3.75%,when the inclination angle of the chute was 15°,25°,35°,45°,and 55°,the mass of maize and wheat mass was 30,50 and 70 kg,the mass of granular compound feed was 30,50,and 65 kg,respectively.It is indicated that it is feasible to use the capacitance method in the online measurement of mass flow rate in the process of transporting granular materials through a chute,which can achieve the automatic online measurement of the mass flow rate of granular materials.

关 键 词：电容 传感器 颗粒物料 质量流量 在线测量 溜管 

分 类 号：S965.211[农业科学—水产养殖]