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  • Peak enhancement factor of the JONSWAP spectrum (12-10-2015)

Peak enhancement factor of the JONSWAP spectrum (12-10-2015)

    WOZ_RVO.nl
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    Asked by WOZ_RVO.nl 655 days ago Answers (1)

    The peak enhancement factor of the JONSWAP spectrum is given as 1.44 for all NSS in Table 4.5 of the metocean report. This is in contradiction to the report text where it is claimed that the peak enhancement factor is determined by the Torsethaugen et al. (1984) method, and furthermore, in section 4.6 of the metocean report it is claimed that a JONSWAP spectrum with peak enhancement factor of about 1.134 is expected to characterize the sea states in the Borssele zone. Please could you clarify which gamma is correct and provide some explanation as to why that value is most appropriate?

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      • WOZ_RVO.nl
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        WOZ_RVO.nl 655 days ago

        This is a typo/inconsistency in the report. None of the printed peak enhancement factors of the JONSWAP spectrum (gamma) is correct. It is recommended to use a gamma value of 2 in general in the BWFZ region given that this estimate (based on the measured Tp / Tm-1,0 ratio) is in our opinion more robust. This value has also been applied in the numerical wave modelling (boundary conditions of SWAN).