Numerical modelling of the biaxial fatigue test of aluminium wheels

The paper is devoted to the numerical simulation of fatigue life of lightweight aluminium wheels subject to biaxial fatigue test. A numerical model based on finite elements is developed for the scope. The model receives as input the test load sequences and outputs the fatigue life of wheel. Two different methods for modelling the load transfer mechanism of the tyre have been analysed, i.e. how the tyre-drum contact forces are transferred to the wheel rim. The first method consists of a simple cosine loading function acting on a fixed arch of the wheel rim. The second method relies on a physical model of the tyre that is fixed at the tyre-rim interface surface; the computed reaction forces are fed as input to the wheel model. The fatigue life of the wheel is estimated by using the Palmgrem-Miner approach. Both the Sines fatigue criterion and the Papadopoulos critical plane with gradient effect criterion are used and the results are compared. Experimental tests have been performed on an actual wheel mounted on the biaxial test bench for a preliminary validation of the method.