Correlation of a Beam-Type Exhaust System Finite-Element Model for Vibration Analysis

A traditional beam-type finite-element model of the automobile exhaust system is shown to only be accurate in predicting the low-frequency rigid-body motion of the exhaust system on the support hangers. The beam-element model is then modified to account for the cross-sectional deformation of the exhaust pipes and is shown to accurately predict the bending vibration up to 300 Hz. The theoretical modification of the beam element model to account for the cross-sectional deformation is described in this paper. Experimental modal analysis tests of an exhaust system installed on a vehicle are conducted to obtain the measured vibration response for experimentally evaluating the accuracy of the model.