Low-Frequency In-cab Booming Noise Reduction in the Passenger Car 2019-26-0171
In-cab booming noise is low frequency (20Hz∼300Hz) phenomenon excites the cabin structure, which occurs mainly due to excitations from the powertrain, exhaust system, road input, etc. Annoyance due to booming noise affects the In-cab sound quality, which results in passenger discomfort. A diesel passenger car observed booming noise issue when operated at stationary as well as dynamic run-up conditions.
In order to increase passenger comfort, experimental root cause analysis conducted on the vehicle to investigate the dominant sources for the cavity boom. Exhaust hanger and one of the engine mount identified as the major reason for booming noise in the cabin. Detailed modal analysis performed on the exhaust system to relocate the mounting and stiffness optimization of rubber hanger studied to improve the vibration transmissibility. Operational measurements conducted on vehicle to confirm the significant booming noise reduction in the cabin.