Abstract
Durability and lifetime requirements are the main reasons why timing drive systems of recent passenger car engines are often equipped with chain drives. From the NVH point of view chain driven systems are usually more critical than synchronous belt-drives. In particular meshing impacts between chain and sprockets as well as impacts in the engagement/disengagement regions of sprockets/guides, lead to a considerable excitation of the engine's structure(whine noise). The MBS modeling of the entire timing drive as a fully coupled system and the assessment of the models validity by measurements of primary dynamics and structural excitation is presented. The influence of selected chain drive's design parameters on structure borne noise is evaluated.