A New Kind of Road Structure-Borne N&V Prediction Method Based on Combination of High-Frequency Parameterized Model of Bushes, Multi-Body Calculation on Adams and Finite Element Model

Road NVH are becoming one of important performance controlled during passenger vehicle NVH development, especially for these EV vehicles due to lack of traditional gasoline or diesel engines noise sources. Generally speaking, traditional CAE and multi-body dynamic approaches have several drawbacks respectively, such as it is extremely difficult to get precise inputs as excitation to CAE model and non-linear parts in suspensions perform complex high frequency dynamic characteristics that is hard to be dealt with in multi-body software. Therefore, structure-borne road noise prediction has become one of difficult NVH problems in vehicle industry and eagerly, needs a systematic and scientific method. Under this circumstance, a new kind of high frequency road N&V co-simulation method has been introduced here to predict road NVH performance for one brand vehicle. This new approach includes three steps. Firstly, dynamic stiffness of bushes in suspension are identified through a new theoretically parameterized model, which combines bush’s dynamic characteristics tests on bench and secondary development tools of applying this model in ADAMS. Secondly, software ADAMS/View and Car modules are used to realize high frequency force transfer calculation up to 100 Hz from wheels knuckle to body via suspensions. Thirdly, a acoustic and structural coupled finite element model is established and that is able to predict road structure-borne noise taking forces in time domain from multi-body calculation results as excitation input. This method includes co-simulation of dynamic bush model, dynamic vehicles model and finite element model and supplements the shortages of current CAE methods for road N&V virtual predictions.