Qualitative Analysis of Film Thickness in Rolling EHD Contact by Fluorescence Technique

Nowadays, it is well known that tribological processes play a significant role in a daily life. The elastohydrodynamic (EHD) regime of lubrication occurs in many applications including both technical and biological points of view. During the last fifty years there was a rapid evolution in experimental methods which help to better understand friction, lubrication and wear. In this study, mercury lamp induced fluorescence is employed to qualitative assess the film thickness in rolling EHD contact created by a steel ball and glass disk. Several experiments were performed to confirm the theory that the dependence between film thickness and entrainment speed should be linear in logarithmic. The results show satisfactory agreement with this prediction, so the method is correct and suitable for further research in the area of EHD contacts. This method also allows analyzing of compliant non-reflective contacts, which will be described in the next paper.