Experimental study and analytical model of bleed valve orifice influence of a high-performance shock absorber on vehicle dynamics

The aim of this study is to model the influence of the bleed orifice area of a high-performance damper on the dynamic behaviour of a vehicle. For this purpose, a mathematical model of a monotube high-performance damper is developed, considering the presence of two regulation ways on the effect of bleed valve orifice of the damper. An application of changes in damper setup in the field of practical enables to analyse the influence of the positions of both rod and bottle selectors on the damping force. The proposed damper model is validated experimentally. The analysis of the dynamic behaviour is performed through a quarter vehicle simulation under different conditions of road roughness and speed regimes. In addition, an analysis of the frequency response of the sprung mass acceleration by means of power spectral density was applied to obtain the dynamic response of the quarter vehicle model. Results show that the influence of the bleed orifice is magnified for low speeds and for profile roads with few variations on surface. This effect is reduced for both the increasing vehicle speed and the profiles with greater difference in irregularities.