Oil film thickness measurement in an internal combustion engine

Included in the objectives of current engine development are minimization of pollutants and the reduction of oil consumption. In order to be able to take measures in achieving these objectives, then along with a number of other factors, it is very important to obtain knowledge of the behavior and the thickness of the oil film between the cylinder wall and piston or piston rings In this respect the upper third of the cylinder bore is of particular interest.