Journal of Korean Society of Coastal and Ocean Engineers (한국해안해양공학회지)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
권호 표지

Computation of Nonlinear Energy Transfer among Wind Seas

비선형 상호작용에 의한 풍파 성분간 에너지 전달의 계산

  • 오병철 (한국해양연구소 연안·항만공학연구센터) ;
  • 이길성 (서울대학교 지구환경시스템공학부)
  • Published : 1999.03.01
Download PDF
⟨ Previous Next ⟩

Abstract

The energy transfer between sea-wave components by way of nonlinear wave-wave interactions plays a central role in spectral evolution. Since huge calculation time is required to exact computation of the resulting Boltzmann integral, however, the exact nonlinear energy transfer has not been directly introduced into operational wave models. Thus, effective calculation methods were examined in the present study which exploit the scale property of a scattering coefficient and the detailed balance of interactions. The improved Webb's method (IWM) has inherent stability because singularities degenerate into a negligible point. The improved Masuda's method (IMM) makes a quasi-analytical treatment of the inherent singularities and requires only 1.3 seconds of computer time via Pentium 300MHz processor. The IMM is, therefore, projected to be very useful for theoretical researches in spectral evolution with fetch- or duration-limited situations.

비선형 상호작용에 의한 풍파 성분간 에너지 전달은 스펙트럼의 발달에서 중요한 역할을 한다. 비선형 전달을 표현하는 Boltzmann적분을 계산하는 데에는 방대한 계산시간이 필요하기 때문에 파랑모형에서 비선형 상호작용을 고려하는 것을 불가능하다. 본 연구에서는 산란계수의 특성과 상호작용의 상세균형의 원리를 이용하여 비선형 전달을 효율적으로 계산하는 방법에 대하여 고찰하였다. Webb의 방법(IWm)은 특이점을 퇴화시켜 매우 안정한 계산 결과를 주지만 상세균형의 원리를 적용할 수 없기 때문에 계산의 효율성에는 한계가 있는 것으로 나타났다. 한편, Masuda의 방법(IMM)에서는 특이점을 해석적으로 처리하며 계산시간은 Pentinum 300MHz Processor에서 1.3초가 소요되었다. 따라서 IMM은 1차원 파랑모형에 실용적으로 사용할 수 있으며 취송시간과 취송거리에 의한 풍파 스펙트럼의 성장 과정 연구등에 매우 유용하다.

Keywords

References

  1. 서울대학교 박사학위논문 비선형 상호작영을 고려한 해양파랑 수치모형 오병철
  2. Proc. Roy. Soc. v.A368 Nonlinear energy transfer in a narrow gravity-wave spectrum Dungey, J. C.;Hui, W. H.
  3. Proc. Roy. Soc. v.A348 On the nonlinear teansfer of energy in the peak of a gravity-wave spectrum Ⅱ Fox, M. J.
  4. Quantum Physics Gasiorowicz, S.
  5. J. Fluid Mech. v.12 On the non-linear energy transfer in a gravity-wave spectrum.Part 1. General theory Hasselmann, K.
  6. J. Fluid Mech. v.15 On the non-linear energy transfer in a gravity-wave spectrum . Patr2. Conservation theorems: wave-particle analogy; irreversibility Hasselmann, K.
  7. J. Fluid Mech. v.15 On the non-linear energy transfer in a gravity-wave spectrum. Part 3. Evaluation of the energy fluk and swell-sea interaction for a Neumann spectrum Hasslmann, K.
  8. Rev. Geophys. v.4 Feynmam diagrams and interaction rules of wave-wave scattering process Hasselmann, K.
  9. Dtsch. Hydrogr. Z.Suppl. v.A8 no.12 Measurements of wind wave growth and swell decay during the Joint North Sea Wave Project(JONSWAP) Hasselmann, K.;Barnett, T. P.;Bousws, H.;Carlson, H.;Cartright, D. E.;Enke, K.;Ewing, J. A.;Gineapp, H.;Hasselmann, D. E.;Kruseman, P.;Meerburg, A.;Muller, P.;Olbers, D. J.;Richter, K.;Sell, W.;Walden, H.
  10. Hamb. Geophys. Einzelschriften, Reihe A: Wiss. Abhand. v.52 A symmetrical method of computing the nonlinear transfer in a gravity wave spectrum Hasselmann, S.;Hasselmann, K.
  11. J. phys. Oceanogr. v.15 Computations and parameterzations of the nonlinear energy transfer in a gravity-wave spectrum. Part I; A new method for efficient computations of the exact nonlinear transfer integral Hasselmann, S.;Hasselmann, K.
  12. J. Fluid Mech. v.97 A similarity relation for the nonlinear energy transfer in a finite depth gravity-wave spectrum Herterich, K.;Hasselmann, K.
  13. Dynamics and Modelling of Ocean Waves. Komen, G. J.;Canaleri, L.;Donelan, M.;Hasselmann, K.;Hasselmann, S.;Janssen, P. A. E. M.
  14. Proc. Roy. Soc. v.A347 On the nonlinear transfer of energy in the peak of a gravity-wave spectrum: A simplified model Longuet-Higgins, M. S.
  15. J. Phys. Oceanogr v.10 Nonlinear energy transfer between wind waves Masuda, A.
  16. The Dynamics of the Upper Ocean(2nd ed.) Phillips, O. M.
  17. Rep. Ins. Geophys. Univ. Hambrug Computations of nonlinear energy transfer for JONSWAP and empircal wind-wave spectra Sell, W.;Hasselmann K.
  18. J. Geophys. Res. v.C98 Implementation of an efficient scheme for calculating nonlinear transfer from wave-wave interactions Snyder, R. L.;Thacker, W. C.;Hasselmann, K.;Hasselmann, S.;Barzel, G.
  19. Ocean Wave Modelling SWAMP Group(24 authors)
  20. J. Phys. Oceanogr v.18 The WAM model A third generation ocean wave predication model WAMDI Group(13 authors)
  21. Deep Sea Res. v.25 Non-linear transfer between sea waves Webb, D. J.
  22. 數値計算に基づく太平洋全域の波浪特性の硏究 日本氣象協會