This noise can be heard as airflow hissing in the window area. It occurs mostly at high speeds, and changes in the vehicle speed or in the direction of the wind alter this noise. Usually the volume of the noise increases with vehicle speed, but the noise occasionally becomes inaudible depending on the wind direction.
Main causes
Air disturbances created by irregularities in the vehicle body
Air leaking through gaps between body panels
Mechanism
1.Noises created by air disturbances due to body irregularities
When air flows over protrusions or recesses on the vehicle surface, air disturbances are created behind them. The noises created by these disturbances then enter the passenger compartment through the doors or windows.
2.Noises created by leaking air
At high speeds, the air pressure outside the passenger compartment is lower than that of the inside. When this air inside is forced out through gaps in the weatherstrips or body panels, and comes into contact with the exterior air flow, noise is generated.
1.Wind noise may occur anywhere, but the four areas shown in the figure are known to be the more common sources.
2.Some of the countermeasures for wind noise are to apply body sealant to the body panel gaps, or to align the doors or windshields.
3.Modern vehicles have less body panel gaps, and thus less wind noise, than older model vehicles.