A frequency-dependent uniform discretization scheme for simulating fluctuating wind field based on a frequency-wavenumber spectrum

Abstract

The frequency-wavenumber spectrum-based spectral representation method (FWS-based SRM) serves as an effective and broadly utilized technique for simulating multivariate fluctuating wind fields. Despite its usefulness, it struggles with accuracy in low frequency range during simulations involving structures of considerable length when employing conventional uniform discretization in both frequency and wavenumber domains. To overcome this challenge, this study introduces a frequency-dependent uniform discretization scheme. This strategy first applies uniform discretization to the frequency domain, and then ascertains the cut-off wavenumbers based on the truncation error, and finally implements uniformly discretization in the wavenumber domain. Subsequently, the uniformly discrete wavenumbers and frequencies are integrated into the FWS-based SRM to generate wind speed time histories, in combination with the FFT technique. The numerical example serves to validate the exceptional accuracy exhibited by the frequency-dependent uniform discretization scheme in low frequency range.