The growth of fetch limited waves in water of finite depth. Part 2. Spectral evolution

摘要

Results showing the evolution of the wave spectrum in finite depth, fetch limited conditions are presented. The data were obtained from a series of eight wave gauges established in shallow Lake George, Australia. The data are well modelled by the previously proposed TMA spectral form and clearly show the transition of the spectra from deep water to depth limited conditions. The TMA parameter of α is found to be a function of the non-dimensional wavenumber, κ but the spectral peak shape parameters of γ and σ appear uncorrelated with κ . The parameter γ is shown to be a function of both non-dimensional fetch, χ and non-dimensional depth, δ. In severely depth limited conditions γ becomes solely a function of δ, increasing in magnitude as δ decreases. Hence, depth limited spectra could be expected to be very peaked compared to deep water counterparts.