KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Development of Numerical Model for Scour Analysis under Wave Loads in Front of an Impermeable Submerged Breakwater

불투과 잠제 전면에서 파랑 작용 하의 세굴 해석을 위한 수치모델의 개발

  • 허동수 (국립경상대학교 해양토목공학과(해양산업연구소)) ;
  • 전호성 (국립경상대학교 해양토목공학과)
  • Received : 2010.01.27
  • Accepted : 2011.06.15
  • Published : 2011.10.31
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Abstract

In this study, the coupled-numerical model has been newly developed to investigate numerically scouring and deposition around a coastal structure like a submerged breakwater using a numerical wave model and a lagrangian particle model for sand transport. As a numerical wave model, LES-WASS-2D (Hur and Choi, 2008) is adopted. The model is able to consider the flow through a porous midium with inertial, laminar and turbulent resistance term and determine the eddy viscosity with LES turbulence model. Distinct element method (Cundall and Strack, 1979), which is able to apply to many dynamical analysis of particulate media, as a lagrangian particle model for sand transport is newly coupled to the numerical wave model. The numerical simulation has been carried out to examine the scour problem in front of an impermeable submerged breakwater using the newly coupled-numerical model. The numerical results has been compared qualitatively with an existing experimental data and then its applicability has been discussed.

본 연구에서는 잠제 주변의 세굴 및 퇴적현상을 수치적으로 모의하기 위해 기존의 수치 파동 모델에 모래입자의 거동 해석을 위한 lagrangian 입자 모델을 결합한 새로운 수치모델을 개발하였다. 수치 파동 모델로서는 파랑에 의한 해저지반 내의 모래입자의 이동과 유동화 해석을 위해 투수성 매체 내부의 유체저항(관성저항, 층류저항 및 난류저항)을 고려할 수 있는 수치모델에 LES 난류모델을 도입한 수치해석기법(허와 최, 2008)을 이용하였다. 또한, 모래입자의 이동해석을 위한 lagrangian 입자 모델로서는 많은 개개의 입자들의 동적해석에 탁월한 개별요소법(Cundall and Strack, 1979)을 적용하였다. 개발된 해석기법을 이용하여 불투과 잠제 전면의 세굴에 대한 수치시뮬레이션을 실시한 후, 기존의 수리모형실험과 정성적으로 비교하면서 그 적용성을 검토하였다.

Keywords

References

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