Dimensional analysis of windscreen noise

It is shown that data on wind noise in spherical and cylindrical windscreens may be represented by a single universal curve if the data are plotted in nondimensional form. Appropriate dimensionless variables are a dimensionless frequency ( fD/V) plotted against a sound pressure coefficient (p̃1/3/ρV2) or a dimensionless spectral density fS/ρ2V4), where f is frequency, D is screen diameter, V is wind speed, p̃1/3 is sound pressure of the wind noise in a 1/3-octave band, ρ is fluid density, and S is spectral density of the wind noise at frequency f. Data obtained from various disparate sources form a single curve with surprisingly small scatter for values of dimensionless frequency ( fD/V) up to 5.