四电极海水电导率传感器设计

Design of four-electrode seawater conductivity sensor

设计了一种新型的基于石英玻璃导流管、金属钛电极结构的四电极海水电导率传感器芯体。从材料选择及分离式的电极结构等方面避免了电极极化效应,提高了检测精度。搭建了两种检测系统,分别对同一温度不同浓度、不同温度同一浓度下的氯化钾溶液进行了测量。确定了电导池常数K为2. 35 cm-1,并给出了25℃时电导率和浓度的关系式。确定了三种不同浓度氯化钾溶液在10~30℃的温度系数,并进行了温度补偿、误差计算,温度补偿后误差在1%以内。结果表明:设计的传感器是一种检测精度较高的、能实时检测待测海水电导率的传感器。

A new type of four-electrode seawater conductivity sensor core is proposed based on quartz glass tube and metal titanium electrode.The material selection of the core and the separating electrode structure avoid polarization effect,and improve detection precision.Two kinds of detection systems are set up to measure conduetivities of potassium chloride solutions in different experimental environments.The first system is designed to measure the conductivities of a variety of potassium chloride solutions at the same temperature,while the second is used to measure the conductivities of the same concentration of potassium chloride solution at different temperatures.Through several experiments and tests,the constant K of conductivity cell is determined to be 2.35cm^-1.Through data analysis and calculation,the relational expression between conductivity and concentration at 25℃ is determined.And the temperature coefficients of three different concentrations of potassium chloride solution at 10-30℃ are given.The temperature compensation error is within 1%.The results show that the designed sensor in a seawater conductivity sensor with high detection precision and real-time detection function.