Identification of the Rear Door Opening Noise in a Passenger Car

In this study, noises generated when opening the rear door of a vehicle are identified, which has recently been receiving renewed attention in the automotive industry. To confirm the characteristics of door opening noise, the noise and vibrations in a rear quarter panel and a rear outer door panel were measured experimentally. Furthermore, the modal testing on these panels was conducted such that the natural frequencies and mode shapes were extracted. By combining not only a noise signal but also the vibration signals and the results of modal testing, the radiation position of the peak frequencies of the door opening noise was identified. Meanwhile, a multi-body dynamics model was established and simulated for a latch system to find the source of the opening noise, and the results of the simulation were verified through simple experiments. We found that a sudden change in the contact force between a claw in the latch system and a striker excites the rear quarter panel and the rear outer door panel, resulting in a door opening noise. In addition, it was also confirmed that the noise increases with the elastic force caused by a deformation of the weather strip.