Research on a semi tubular lubricating oil water content measurement device based on dielectric constant

In order to improve the accuracy and responsiveness of the dielectric constant based capacitive sensor in detecting lubricating oil, a semi tubular capacitive sensor based on dielectric constant measurement is designed and improved in this paper. The sensor adopts a semi tubular structure, which was the reasonable structure, strong stability. The sensing area should strengthen the faster flow of lubricating oil, so it will improve the response speed and accuracy of online water content measurement. Based on capacitance detection and the structure of the sensor capacitance probe, the theoretical solution of the designed sensor capacitance is derived using the equivalent diameter assumption. At the same time, the article has discussed the changes and characteristics of capacitance when temperature was changed, as well as the impact of edge effects on capacitance measurement. The capacitive sensor has a simple structure and can effectively detect the water content of lubricating oil, which has a good engineering application value.