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Wave statics. Chang Hsien Kuo. 國立交通大學土木工程學系 中華民國 102 年 3 月 28 日. Reference. methods. Significant wave representation . Individual wave H 1 >H 2 >H 3 …. Brestchneider (1968) H 1/3 : 前 1/3 大之個別波波高平均值 (significant wave, 示 性 波 ) T 1/3 : 相對於大小排序波高之 週期平均值 Neir et al. (2003)
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Wave statics Chang HsienKuo 國立交通大學土木工程學系 中華民國102年3月28日
Significant wave representation Individual wave H1>H2>H3… Brestchneider (1968) H1/3:前1/3大之個別波波高平均值 (significant wave, 示性波) T1/3:相對於大小排序波高之週期平均值 Neir et al. (2003) T1/3:T1>T2>T3…週期仿照示性波高前1/3大之平均值週期
Statistical properties Rayleigh distribution
Frequency spectrum of irregular waves Fourier transform (Fast FT)
Frequency spectrum of irregular waves Brestchneider (1968) Wallops spectrum by Hwung et al . (1981) Goda (1988)
Frequency spectra of irregular waves JONSWAP (1973)
Directional Spectrum of sea waves G(θ) : directional distribution of energy spectrum S(f) : energy (power) spectrum
Directional Spectra of sea waves Mitsuyasu (1975) Smax: Spreading parameter
Directional Spectra of sea waves Smax=20
Relationship between spectra and wave height Zeroth moment of spectrum
Relationship between spectra and wave period Zeroth and second moments of spectrum
Example I Directional spectrum
Example-I sample average of sixteen directional spectra directional spectra of in-site buoy measurements
Example-I Power spectrum directional spreading function