Contact modeling for joints in aircraft engines

Markus Gitterle, Alexander Popp and Michael W. Gee

Fan and turbines in aircraft engine consist of the rotating disc and a large number of blades mounted into it. These joints are a conventional dovetail for the fan and a multiple lobe dovetail, also known as firtree, for the turbine.

The phenomenon of "fretting fatigue" is a complex damage mechanism. It can occur where components are in frictional contact and subjected to small oscillatory movements. This results possibly in surface degeneration due to wear. Cracks can appear in the damaged regions propagating into the the thermally loaded components and leading to their failure.

Numerical simulations contribute generally to the understanding of these effects and especially to lifetime prediction of the mentioned components in aircraft engines. At our institute, we are heading mainly towards state-of-the-art methods in contact dynamics, contact with wear and thermo-mechanical contact.

Research in these fields happens within the project "Enhanced contact modeling for turbine disc firtrees" together with Rolls-Royce Germany, Ltd & Co KG. It is funded by the aeronautical research program "Lufo" with its project "RobusTurb" from the German Federal Ministry of Economics & Technology.