Water for future (물과 미래)

Korea Water Resources Association (한국수자원학회)
권호 표지

Analysis of the Hydraulic Behaviour in the Nearshore Zone by a Numerical Model

수치모형에 의한 연안해역 해수운동의 분석

  • 이희영 (서울시립대학교 공과대학 토목공학과) ;
  • 정선길 (서울시립대학교 공과대학 토목공학과)
  • Published : 1994.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

The unproper development of the nearshore zone can enhance the diffusion of pollutant in the nearshore zone resulting in unbalanced sediment budget of beach which causes alteration of beach topography. Therefore, it is required to predict the effects of the envirnmental change quantitatively. In this paper, the depth-averaged and time-averaged energy balance equation is selected to acount for the wave transformation such as refraction, shoaling effect, the surf zone energy disipation, wave breaking index and bore, due to wave breaking in the shore region.(Numerical solutions are obtained by a finite difference method, ADI and Upwind. For the calculation of the wave-induced current, the unsteady nonlinear depth-averaged and time-averaged governing equation is derived based on the continuity and momentum equation for imcompressible fluid.) Numerical solutions are obtained by finite difference method considering influences of factors such as lateral mixing coefficient, bed shear stress, wave direction angle, wave steepness, wave period and bottom slope. The model is applied to the computation of wave transformation, wave-induced current and variation of mean water leel on a uniformly sloping beach.

확산현상, 표사유동 및 인간의 여러 활동이 실제 연안해역에서 일어나므로 연안해역 해수운동의 물리적 특성을 파악하고 해석하는 것은 중요한 의미를 지닌다. 본 연구에서는 연안해역에서의 파랑변형과 평균해수위 변동 그리고 연안유속 분포양상에 대해 여러 인자들이 미치는 영향을 2차원 유한차분 모형(ADI, Up-wind)을 이용하여 분석하였다. 계산결과로는 수치모형을 해저경사가 일정한 2차원 지형에 적용하여 해저경사, 입사파고, 파향각, 파주기, 마찰계수 및 수평확산계수가 연안해역 특히 쇄파대내에서 파랑변형, 평균해수위 변동 및 연안유속 분포에 미치는 영향을 분석하였다.

Keywords

References

  1. Proc. 17th Coastal Eng. conf. Numerical modeling of nearshore circulation Ebersole,B.A.;Dalrymple,R.A.
  2. Wave attenuation and wave set-up on a coastal reef Franciscus Gerritsen
  3. Nearshore Dynamics and Coastal Processes Horikawa Kiyoshi
  4. J. of Geophysical Research v.75 Longshore currents generated by obliquely incident sea waves 1 Longuet-Higgins
  5. J. of Geophysical Research v.75 Longshore currents generated by obliquely incident sea waves 2 Longuet-Higgins
  6. Deep-Sea Research v.11 Radiation stresses in water waves; a physical discussion with applications Longuet-Higgins;Stewart,R.W.
  7. Coastal Engineering A numerial model of nearshore currents based on a finite amplitude wave theory Masatak Yamaguchi
  8. Coastal Engineering A numerial model of nearshore currents due to irregular waves Masatak Yamaguchi
  9. The Applied Dynamics of Ocean Surface Waves Mei,Chaing C.
  10. Proc. 29th Japanese Conf. on Coastal Eng. Numerical simulation of the nearshore circulation Nishimura,H.
  11. Coastal Engineering in Japan v.28 On the numerical computation of nearshore currents Nishimura Hitoshi;Maruyama Kohki
  12. J. Geophysical Reserch v.79 Wave-induced nearshore circulation Noda,E.K.
  13. Coastal Engineering in Japan v.27 Reproduction of nearshore currents by mathmatical model Tanaka Hiroyoshi;Wada Akira
  14. Mathematical modeling of wave-current interaction flow in shallow waters Yoo,D.H.
  15. Coastal Engineering Wave and current interactions in shallow water Yoon,S.B.;Philip L.F.Liu