摘要
设计一种变介电常数型电容式液位传感器,通过对不同宽度电极下传感器输出电容与对应液位的实验数据分析,发现传感器灵敏度随电极宽度的增加而近似线性提高;同时,发现传感器灵敏度与液位下降速度相关。建立传感器数学模型,分析影响传感器灵敏度的因素和机理。研究结果表明:以范德华力附着在瓶壁内侧的吸附水在电场作用下极易极化,会引起其介电常数超常增大;吸附水对传感器的灵敏度有直接影响。
A variable-dielectric-constant capacitive sensor is designed.The experimental data are obtained through the use of electrodes of different width.By analyzing the correlation between them,it is found that the sensitivity of the sensor is nearly linear along with increasement of the electrode width and affected by the speed of infusion.The model of the sensor is presented and then the affecting factors and mechanism on the sensitivity are discussed.It is showed that water absorbed on the inside wall by molecular force is easily polarized,making the dielectric constant abnormally increase, which makes absorbed water have significant effect on the sensitivity.
出处
《传感器技术》
CSCD
北大核心
2004年第8期9-11,共3页
Journal of Transducer Technology
关键词
电容式传感器
吸附水
电极
静脉输液
极化
capacitive sensor
absorbed water
electrode
vein infusion
polarization
