Characterization of Lubricating Oil Using Ultrasound

Abstract

This paper presents an ultrasonic method to measure small concentrations of water in lubricating oil. It uses an ultrasonic measurement cell composed by a piezoceramic emitter (5 and 10 MHz), and a large aperture PVDF receiver that eliminates diffraction effects. The propagation velocity, attenuation coefficient and density of several samples of water-in-oil emulsion were measured. The concentrations of water of the samples were in the range of 0 to 5% in volume, and the results showed that these low concentrations can be discriminated within a resolution of 0.2% in the studied range, using the measurement of the propagation velocity

Temperature and Pressure Dependences of Thermophysical Properties of Some Ethylene Glycol Dimethyl Ethers from Ultrasonic Measurements

“…Another possibility is to measure acoustic parameters such as the propagation velocity, attenuation coefficient, and acoustic impedance, using ultrasound. These parameters can be used to nondestructively evaluate variables of industrial processes, such as the concentration of particles in emulsions and suspensions [46] and lubricant film measurements.…”

Ferroelectret-based Hydrophone Employed in Oil Identification—A Machine Learning Approach

“…The acoustic waves are then monitored according to acoustic parameters such as the speed of propagation, attenuation, acoustic impedance, and these parameters can be related to some physical properties of the environment, such as density, viscosity and elasticity. One of the advantages of this technique is that it can be used to indirectly evaluate variables of industrial and research processes in a non-destructive way, with the possibility of non-invasive and online applications [30].…”