A Filter Seal Model for Point Mobility Prediction of Air Induction Systems 2006-01-1209

Virtual design validation of an air induction system (AIS) requires a proper finite element (FE) assembly model for various simulation based design tasks. The effect of the urethane air filter seal within an AIS assembly, however, still poses a technical challenge to the modeling of structural dynamic behaviors of the AIS product. In this paper, a filter seal model and its modeling approach for AIS assemblies are introduced, by utilizing the feature finite elements and empiric test data. A bushing element is used to model the unique nonlinear stiffness and damping properties of the urethane seal, as a function of seal orientation, preloading, temperature and excitation frequency, which are quantified based on the test data and empiric formula. Point mobility is used to character dynamic behaviors of an AIS structure under given loadings, as a transfer function in frequency domain. Point mobility can also be conveniently measured by using an instrumented hammer and accelerometer, and thus used for the correlation of CAE and test results as well. CAE predictions of point mobility results of AIS assemblies, with various design configurations, are investigated to determine the validation of the proposed filter seal model, based on the correlation of the predicted results with their respective experiment ones.

CAE simulation based design examples are presented to demonstrate the benefits of the AIS assembly model, by employing the developed modeling and analysis approaches. In addition to point mobility prediction, the application examples also include the normal modal analysis for stiffness evaluation of AIS assembly products, the dynamic acceleration and stress response simulation for virtual design validation tests, and the fatigue damage evaluation based on dynamic stress and material S-N damage model for durability performance.