Search Results

One measure of perceived quality in a new car is how easily the passengers can communicate. This includes communication between the passengers and also communication to the vehicle itself, as features such as Bluetooth and voice activated controls become increasingly common. Articulation Index (AI) has long been the standard in the automotive industry for evaluating the ease of communication. Previous studies have explained that AI, however, only evaluates the background noise that surrounds the listener; and does not capture changes in modulation of sound before reaching the listener. The telecommunication and construction industries have used Speech Transmission Index (STI) as a measure of communication. This method incorporates the masking effect of background noise, and modulation of the speech signal along the transmission path. This study focused to understand STI, cascade to component characteristics and modify characteristics to improve speech transmission inside vehicles.

With the introduction of hybrid vehicles and the associated elimination of engine and exhaust masking noises, sounds from other sources is becoming more noticeable. Fuel tank sloshing is one of these sources. Fuel sloshing occurs when a vehicle is accelerated in any direction and can create noise that may be perceived as a quality issue by the customer. To reduce slosh noise, a fuel tank has to be carefully designed. Reduction in slosh noise using test- based methods can be very costly and timely. This paper shows how, using the combination of CFD (Computational Fluid Dynamic), FE (Finite Element) and Acoustic simulation methods, the radiated fuel tank slosh noise performance can be evaluated using CAE methods. Although the de-coupled fluid /structure interaction (FSI) method was used for the examples in this paper, the acoustic simulation method is not limited to the decoupled FSI method.