Current simulation tools for the investigation of the dynamic system response as well as for the component stresses on the basis of multi-body and finite-element techniques are integral part of today's powertrain development efforts. These tools are typical used for the analysis and optimization of shafts, clutches, chain/belt drives, bearings, levers, brackets, housings and many other components.
An exception is made by gears which today are still frequently investigated by the help of semi-empirical methods based on DIN, ISO, AGMA and the specific knowledge base of well experienced developers. The main difficulty is that the gears are rolling off via large contact surfaces with complex nonlinear mechanical contact properties.
Within the scope of research work FEV developed a new method for the analysis and optimization of gear drives based on comercial multi-body and finite-element software platforms. Due to a realistic roll-off contact description for each pair of teeth incorporating the detailed geometric surfaces and the complex nonlinear contact situation the variating tooth load and stresses can continuously be determined during the roll-off procedure. Influences of modifications of the tooth profile and along the tooth width including the tolerances can be registered by this. Therefore a realistic dynamic system behaviour is inherent to this kind of gear train modelling.
This report summarizes the current virtual powertrain development methods and details the modern gear train simulation approach for the main powertrain components namely the engine and the transmission.