Wheelflat impact noise prediction using detailed contact model

Jiannan Yang , David Thompson

Impact noise, which has a similar excitation mechanism to rolling noise, is caused by rail and wheel discontinuities. However, the requirements for the use of a Hertzian contact model are not fulfilled due to large variations of the contact geometry at the discontinuity such as a wheelflat. Therefore, a detailed numerical contact model is included dynamically in the wheel/rail interaction model to predict the impact noise due to a wheelflat. The contact patch size is discretized adaptively at each time step to ensure that all the contact points are included. The impact force can be predicted up to about 3 kHz. For noise prediction, the equivalent roughness from a linearized frequency domain model is obtained from the predicted impact force. The TWINS model is then used to generate the sound power spectrum from the equivalent roughness. Roughness input data from SNCF field measurements on a wheelflat is used to validate the model in terms of track vibration and pass by noise.

Mots clés: railway noise; wheelflat; contact; TWINS

Domaines: Acoustique [physics.class-ph]

Jiannan Yang, David Thompson. Wheelflat impact noise prediction using detailed contact model. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00810941⟩