微波同轴腔介质厚度测量理论分析  

Theoretical Analysis of Medium Thickness Measurement by Microwave Coaxial Resonant Cavity

作　　者：钱江波[1] 韩中合[1] 严晓哲 

机构地区：[1]华北电力大学电站设备状态监测与控制教育部重点实验室,保定071003 [2]广东省特种设备检测研究院,佛山528251

出　　处：《工程热物理学报》2015年第8期1732-1736,共5页Journal of Engineering Thermophysics

基　　金：国家自然科学基金项目(No.51076044);中央高校基本科研业务费项目(No.13MS93)

摘　　要：汽轮机动静叶片处的水膜、风机桨叶上的冰层等介质厚度的在线准确监测,对电力工业的安全生产具有重要的指导意义。采用微波开式同轴谐振腔作为介质厚度测量传感器,建立了介质厚度测量数学模型,根据谐振腔等效电路,推导了介质厚度的测量关系式。分别设计了用于水膜、冰层厚度测量的传感器。结果表明,随着介质厚度增加,谐振腔的谐振频率减小,衰减增大,且随着谐振腔的基准谐振频率变大,谐振腔的厚度测量分辨力提高。水膜、冰层厚度测量传感器的测量范围分别为0~1 mm、0~10 mm,测量精度较高,结构简单,易于布置,可实现在线监测。微波同轴腔在线测量介质厚度是可行的。Real-time monitoring medium thickness such as water film of rotor and stator blade of turbine,deposition ice of wind driven generator,has a significant guide meaning to the safe operation of power industry.The mathematical model of medium thickness measurement is established and the thickness measurement equation is deduced,based on equivalent circuit of resonant cavity.Water film and ice thickness measurement sensor are designed respectively.The results showed that resonance frequency of resonant cavity decreases and attenuation of resonant cavity increases with medium thickness increase.The thickness measurement resolution improves with the benchmark resonance frequency of resonant cavity increase.The measurement range of water film sensor is 0~1 mm and the measurement range of ice is 0~10 mm.The structure of sensor is simple and has a high accuracy.The technology of coaxial resonant cavity method for measuring medium thickness is reliability.

关 键 词：微波测量 谐振腔 厚度测量 液膜 冰层 

分 类 号：TK83[动力工程及工程热物理—流体机械及工程]