Riassunto analitico
The fatigue behavior of a gear pair is an important topic regarding safety and performance in a high performance vehicle. The purpose of this thesis is to define, by a finite element simulation, a proper methodology to analyze the fatigue behavior of a gear pairs in order to maximize the performance but with no safety issues.
First of all it has been selected the optimal meshing strategy for a gear. in order to do that the aim considered is to have a refining in the most interesting zone for the safety factory, but also less refined zone in order to guarantee a faster simulation.
When a proper and optimal meshing strategy has been defined, then it has been set a static finite element model to process and analyze the contact and the force acting in the gear pairs.
Starting from the static analysis, a full fatigue cycle with the proper boundary and initial condition has been simulated. The fatigue analysis has been done with the multiaxial Dang Van criterion.
It has also been investigated the minimum time step to apply at the simulation to capture the complete load history and also to have the simulation as faster as possible.
Afterwards it has been analyzed the influence of different element of the transmission such as shaft, bearing and the reaction force from the other gears in contact. To do this all the parts are meshed and the result compared to the case in which they are just simplified.
Once the full methodology has been developed, a final and complete finite element analysis simulation including the microgeometry has been done.
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