An Investigation of People's Responses to Automobile Wind Noise with Gusts

Improved models of wind noise perception are being developed to aid automobile manufacturers in designing cars with satisfactory interior noise levels. An expanded acceptance model of stationary wind noise having already been produced, the current goal is to model acceptance of non-stationary noise, such as would be expected in a car subjected to unsteady wind conditions on the road. Initial subjective tests in this area are limited to examining people's reaction to simpler gusting scenarios. A set of test sounds was generated using a program that simulates time-varying wind noises based on the time-varying speed and direction of the incident airflow. The airflow pattern on which the sounds were based contained a series of consecutive gusts preceded and followed by steady wind. The number, duration, and strength of the gusts was varied between sounds. Based on the results of the listening study, a preliminary "gusting metric" was proposed that determines an acceptance penalty for the sound based on the behavior of the gusts. This metric may be appended to existing stationary-noise models to produce a composite acceptance model. The current limitations of the gusting metric are discussed, and prospective revisions and expansions are described.