DETERMINATION OF THE VISCOSITY PARAMETERS FOR AN ULTRA THIN LIQUID LAYER IN LUBRICATION

摘要

This paper presents a new method for the estimation and, consequently, a new method of liquid viscosity measurements for non-Newtonian liquids retained in ultra thin layer. Essentially the test stand consists of a Piezoelectric Tuning Fork (PTF) and an Atomic Force Microscope (AFM). This method is to be based on the measurements of the amplitude values of PTF vibrations inside the liquid region using AFM and other devices described in this paper. Vibration implies a share rate in liquid and this implies changes of the apparent viscosity of non-Newtonian liquids. During measurements, the ultra thin layer of liquid is laying on the solid substratum. This solid substratum imitates the superficial layer on cooperating bearing surfaces. Experimental measurements prove that the physical properties of superficial layers have a significant influence on the liquid viscosity in ultra thin liquid layers. Viscosity changes within ultra thin layer in relation to height.