ONLINE MONITORING OF LUBRICATING OILS FOR COMBUSTION ENGINES USING ELECTRICAL SENSORS

The deterioration of lubricating oils in internal combustion engines c an be evaluated by various parameters like viscosity, total base numbe r (TBN), humidity and solids content, produced by abrasive wear. The e xperiments are aimed to design a capacitive sensor for online measurem ents in cars in order to substitude extensive external analysis. The s ensoring principle is based by the interdependence between oil deterio ration or variance in the lubricant characteristics and electrochemica l impedance spectroscopy (EIS) data. The present article shows the sen sor principle, the sensor construction, the measuring method, the eval uation of the sensor signals and first results. Correlations between t hese results and values of chemical and physical reference measurement s are discussed.