The urge and demand for less CO2-emissions in  automotive traffic continue to be undiminished. Automobile manufacturers try nowadays to build up a powertrain that inherently causes less loses. A current weak point are idling conditions of wet clutches, which are part of nearly every higher class automobile. The relative velocity difference between the driven and driving side and the existence of oil in the submillimetre gap between these plates produces losses, due to shearing. The reduction of this so called drag torque is still an unsolved problem, due to a difficult access for experimental measurements methods on one side and the lack of an accurate model, which considers the fluid flow in between the gap without an oversimplification on the other. Nowadays mostly integral torque measurements serve as basis for development and estimation.

At istm a combination of different velocity measurement techniques like Particle Image Velocimetry (PIV), Particle Tracking Velocimetry (PTV) and Laser Doppler Velocimetry (LDV) tries to uncover the formerly hidden flow patterns in the sub-millimetre gap.

The aim of this project is to derive meaningful and high-precision velocity information which helps to develop a prediction model which is capable in delivering more precise data.