Authors: Peter Holen, Mathias Zellinger
Addresses: SCANIA, SE-151 87 Sodertalje, Sweden. ' SCANIA, SE-151 87 Sodertalje, Sweden
Abstract: This paper investigates how attachment compliance coming from mounting bushings or brackets affects damper efficiency. Analyses with a simple mass-spring-damper system show that compliance in damper-attachment points reduces the damper efficiency. If however vibration isolation of the mass is considered, it may be seen that compliance increases low frequency vibrations but reduces high frequency vibrations. Through analyses of this system, the relative damping ratio is studied as a function of excitation frequency and attachment stiffness. Numerical values of typical damper-attachment stiffness in heavy vehicles are furthermore obtained from both static finite element (FE) analysis of the chassis frame and from dynamic FE analysis of a tractor. The effect damper-attachment compliance has on vehicle behaviour is finally quantified with MBS simulations of a tractor semi trailer combination. It is found that attachment stiffness should be considered when simulating load cases containing high frequency inputs.
Keywords: damper attachment compliance; heavy vehicles; hydraulic dampers; parameter extraction; relative damping; vehicle suspension systems; damper efficiency; vibration isolation; damping ratio; excitation frequency; attachment stiffness; finite element analysis; FEA; modelling; vehicle behaviour; tractor semi trailer; simulation.
International Journal of Vehicle Design, 2006 Vol.40 No.1/2/3, pp.77 - 92
Available online: 21 Dec 2005 *Full-text access for editors Access for subscribers Purchase this article Comment on this article