A new concept for the damping of heavy automotive structures Un nouveau concept pour l'amortissement de composantes automobiles de fortes epaisseurs

摘要

Damping devices are widely used to enhance the vibratory and acoustic behavior of vehicle components. The most known device is damping sheets (or liquid applied sound deadener) applied on bare steel panels to lower the vibration levels by a combined mass and damping effect. This kind of solution can be improved by using constrained layer damping materials. But in many cases the applications are limited to light and/or soft panels. For heavier components, like subframe parts (axle, engine cradle…) the use of this kind of damping device is quite impossible because of the steel thickness (a few millimeters). For such components, the effect of a free layer damping is neglectable. The damping material must be constrained by a top layer having an equivalent flexural stiffness compared to the structure to be damped to deform the visco-elastic material sandwiched between the two stiff layers. In summary, the damping device can be as heavy as the component of the structure to be damped leading to heavy solutions which are usually not acceptable. The aim of this article is to present the Damping Deformable Device concept as a solution for the dampening of these heavy structures (3D concept).