Understanding Wind Noise
Aeroacoustic noise is a difficult topic and its theory is still under development...
Aeroacoustics is a branch of acoustics that studies noise generation through either turbulent fluid motion or aerodynamic forces interacting with surfaces. Noise generation can also be associated with periodically varying flows. An example of this is the Aeolian tones produced by wind blowing over fixed objects.
Although no complete scientific theory of the generation of noise by aerodynamic flows has been established, most aeroacoustic analysis relies upon the so-called acoustic analogy, proposed by Sir James Lighthill in the 1950s while at the University of Manchester (Aerodynamic Generation of Sound) whereby the governing equations of motion of the fluid are coerced into a form reminiscent of the wave equation of "classical" (i.e. linear) acoustics in the left-hand side with the remaining terms as sources in the right-hand side...
Measuring aeroacoustic noise with both external and in-canal microphones.
Measuring targeted wind flow noise at different head / ear locations and velocities.
Measuring turbulent pressure fluctuations and correlating to in ear wind noise measurements.
Smoke flow visualization / laser light imagery and fluorescein dye visualization / laser light imagery
Constructive testing and analysis. Adding and subtracting different parts of the ear using modeling clay.
Hot wire and static / dynamic pressure probe anemometers. Measuring and mapping flow / velocity patterns.
Understanding wind noise helps us develop the most effective products.