Optimization of Exhaust Hangers Location Layout by Vibration Transfer Function

Abstract:

An optimization method about layout of exhaust hangers location was presented by vibration transfer function(VTF). Mathematical model of the VTF from engine excitation to exhaust was established with finite element method by taking the layout of hangers location in a hybrid electric vehicle(HEV) as an example. Then summation of relative displacement response of points on the exhaust was calculated in range of vibration frequencies. Finally, an optimized layout was obtained on the basis of the minimum of the summation of relative displacement response. The results indicate that the hanger location is decided by engine excitation, modal participation factors and modal vectors of powertrain and exhaust together in the VTF method. It was proved that vibration accelerations of the exhaust and rail of seat in the optimization layout reduced by more than 17% in comparison with the initial one based on the test data of t he HEV. So the optimization method about layout of hangers location by the VTF can be resorted to hanger location design.

Key words:exhaust; vibration transfer function; hanger location; summation of relative displacement response