An Optimization Model of Noise and Vibration in Passenger Car Cabin

Car cabin acoustical comfort is one of the factors which attract the buyer prospective buyer on purchasing a new vehicle. Basically the amount of discomfort depends to magnitude, frequency, direction and also the duration of exposed vibration in the cabin. The comfort of the driving influences driving performance. Generally the vibration is caused by two main sources: engine transmission and interaction between tyre and road surface. In this study the effects of vibration to noise in passenger car cabin were investigated. Vehicle acoustical comfort index (VACI) was used to evaluate the noise annoyance level and vibration dose value (VDV) was used to evaluate the vibration level. By referring to the noise and vibration trend to engine speeds, an optimization model was built to find the optimal VDV value against the engine speed in order to obtain required maximum noise (VACI) in the passenger car cabin. Thus, a VACI-VDV reference table formed to assist automotive researchers to reduce the vibration and at the same time to reduce noise annoyance level in passenger car cabin.