Calculated wind noise for semi-porous fabric domes

Abstract

A simple calculation of the wind noise measured at the center of three 2 m diameter semi-porous fabric domes is developed. The calculation provides a model of the measured wind noise and is based on the model for a large porous wind fence enclosure. The model combines the wind noise contributions from (a) the turbulence-turbulence and turbulence-shear interactions inside the domes, (b) the turbulence interactions on the surface of the domes, and (c) the turbulence-shear interactions outside of the domes. Each wind noise contribution is calculated from the appropriate measured turbulence spectra, velocity profiles, correlation lengths, and the mean velocity at the center, surface, and outside of the enclosure. The model is verified by comparisons of the measured wind noise to the calculated estimates of the differing noise contributions and their sum. The calculated estimates indicate that the principle source of low frequency wind noise at the center of the domes is due to the turbulence interactions on t...