Long Term Ride Dynamics of Large Order Vehicle Models With Nonlinear Suspension

This work presents a systematic methodology for investigating long term ride dynamics of large order vehicle models in a computationally efficient way. First, the equations of motion for each of the main structural components of the vehicle are set up by applying finite element techniques. The resulting composite models possess strongly nonlinear characteristics and as their order increases the existing numerical methodologies for a systematic determination of their dynamics become inefficient to apply. Therefore, the first step of the present methodology is to reduce the dimensions of the original system by applying a suitable component mode synthesis approach. Subsequently, this allows the application of appropriate numerical methodologies for predicting response spectra of the nonlinear models to periodic road excitation. Results obtained by direct integration of the equations of motion are also presented. The accuracy and validity of the applied methodology is verified by comparison with results obtained for the original models. The frequency ranges examined are useful for studies referring to both ride and acoustics response of the vehicle.