Simple Optical Method for Measuring Oil-Mist Lubrication

Oil-mist is often used for minimum quantity lubrication of mechanical tools. For the measurement of the oil flow, inside compressed air, we propose a simple optical sensor, realized by a led source and a photodiode. The scattering spectrum, due to the oil particles, provides information about oil percentage and flow speed. The system is described by simulations and experimentally verified. The implemented algorithm allows for real-time measurements, with a low-cost microcontroller. The sensor characterization demonstrates performances and reliability adequate for industrial applications.