To analyze vibration generated from the gears caused by meshing error, a new prediction methodology has been developed for vibration transmitted through the engine mounts from the transmission housing. This paper focuses on the left engine mount and brackets attached to the transmission housing of a compact front-wheel drive (FWD) vehicle that connect the transmission housing to the body structure. In this methodology, a modeling technique that incorporates the dynamic characteristics of rubber mounts and brackets is indispensable.
A new simulation technique deals with a detailed rubber mount FE model that considers the contact area at the attachment point of the mount and brackets. The methodology is able to estimate vibration with high accuracy by taking into account dynamic characteristics such as surging for the rubber mount, and using the actual contact area confirmed by pressure sensitive paper for the vehicle FE model.
Using this methodology, the vibration transmitted through the left engine mount to the body was predicted with the transmission bracket, body bracket, and mount rubber in an assembled state. To confirm the validity of the methodology, the vibration was predicted with different rubber mount hardness values. A close correlation between the transfer functions in the experiment and CAE was confirmed.