混药质量浓度在线检测装置

Online Detector of Pesticide Mixing Concentration

根据溶液质量浓度不同,其折光率不同的原理,设计了一种混药质量浓度在线检测装置。采用波长650 nm二极管激光器作为光源,PSD作为光斑位置探测器,设计和制造了有机玻璃材质的三角形检测管和以OPA4277芯片为主的信号调理电路。在流量为4.7、5.4和6.1 L/min时得到的光斑位置与质量浓度拟合曲线的决定系数R2均大于等于0.983 1,且随着流量的减小,其拟合曲线的决定系数逐渐增大。在流量为6.1 L/min时,在线测量混药质量浓度存在最大偏差为0.075 1 g/L,平均相对误差为8.99%。表明该装置可用于混药质量浓度的在线检测。

An online detector of pesticide mixing mass concentration was developed based on the fact that different concentrations of solution had different refractive index. A 650 nm diode laser was used as the light source and a PSD as the light spot position detector. A PMMA triangular detector tube and a signal adjustment circuit based on 0PA4277 chip were designed and manufactured. The experimental results showed that at the flow of 4.7, 5.4 and 6.1 L/min, the determination coefficient of position/ concentration fitted curves were all above or equal to 0. 983 1, and it increased with the flow decreased. At the flow of 6.1 L/rain, the maximum deviation was 0. 075 1 g/L and the average relative error was 8.99% , which showed that the developed detector could be applied to mixing mass concentration online detection.