- The main focus of the project series “Piston Ring Oil Transport” is the investigation of the tribological conditions in the piston assembly. Within the first part of the project, a 0.5-l single-cylinder research engine was built up [1, 2], which is equipped with numerous sensors to measure the tribological circumstances. In the second project part [3] presented here, additional simulation models are developed, which gain accuracy compared to the recorded measurement data and contribute significantly to an understanding of the oil supply at the piston assembly.