基于驻波原理的锥式林区土壤含水率仪设计与性能分析  

Design and Performance Analysis of Cone-type Forest Soil Moisture Sensor Based on Standing Wave Principle

作　　者：田昊[1,2] 刘卫平[1,2] 赵燕东[1,2] TIAN Hao;LIU Weiping;ZHAO Yandong(School of Technology,Beijing Forestry University,Beijing 100083,China;Beijing Laboratory of Urban and Rural Ecological Environment,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学工学院,北京100083 [2]北京林业大学城乡生态环境北京实验室,北京100083

出　　处：《农业机械学报》2018年第8期194-202,共9页Transactions of the Chinese Society for Agricultural Machinery

基　　金：中央高校基本科研业务费专项资金项目(2015ZCQ-GX-04);国家重点研发计划项目(2017YFD0600901);北京市科技计划项目(Z161100000916012);城乡生态环境北京实验室(北京市重点)项目

摘　　要：为了提高现有土壤含水率传感器在林区的测量性能及可使用性,在优化传感器结构的基础上,设计了一种基于驻波原理的锥式林区土壤含水率仪,其锥角30°、探头直径20 mm、探头长度150 mm。实验结果表明:传感器横向测量范围为10 cm、纵向测量范围为18 cm,输出线性拟合决定系数在0.96以上。静动态特性分析表明,传感器测量范围为零到粘壤性土壤饱和含水率,测量精度为3%,稳定性标准差0.49%,超调量为0.48%,过渡时间0.582 s。通过与TDR(TRIME-HD2型传感器、德国)进行对比,测量结果线性拟合决定系数在0.97以上,两者测量性能相当,表明所设计的传感器能够达到实际使用的要求。本文设计的土壤含水率仪性价比更高,更适用于林区土壤含水率测量,使用更为便捷。The soil in forest area is more complicated than the soil in farmland,and the performance structure of real-time measuring instrument of water content is more demanding,in order to improve the measurement performance and usability of the existing soil moisture sensor in the forest area,on the basis of optimizing the sensor structure,the cone-type forest soil moisture sensor was designed based on standing wave principle. Cone angle was 30°,probe diameter was 20 mm and probe length was 150 mm.The transverse impact scope of the sensor was 10 cm and vertical scope was 18 cm,and the output linear fitting decision coefficient was over 0. 96. Static and dynamic analysis showed that the measurement range of the sensor was from zero to saturated soil moisture content of clay soil,the measurement accuracy was3%,the stability standard deviation was 0. 49%,the overshoot was 0. 48% and the transition time was0. 582 s. The linear fitting determination coefficient of the measurement results was above 0. 97 by comparing with TDR（TRIME-HD2,Germany）,the results of the two measurements were basically the same,and the results showed that the designed sensor met the actual application requirements. But the designed sensor was more suitable for measuring soil moisture in the forest area and more convenient to use,it provided an effective means for forest tending and forest ecological monitoring.

关 键 词：土壤含水率仪 驻波原理 林区 设计 

分 类 号：S237[农业科学—农业机械化工程]