This study shows the role of waves, tide, storm surge and river discharge which impact on water level variation in Suyeong bay. Suyeong bay has a narrow inlet channel where is flood dominance caused by rainfall. The effect of typhoons which make a serious
Boussinesq 모형을 이용하여 규칙파 조건(Regular wave condition)에서 파랑변형 및 해빈류의 수치모의를 하였다. 파랑변형의 수치결과는 선행 연구에 의한 수리실험 결과와 비교하여 매우 좋은 일치를 보였으며, 검증한 파랑변형 결과를 바탕으로 충분히 안정한 상태 이후의 해빈류를 계산하여 예측하였다. 모형의 현장 적용성을 위해, 실규모해역에서 관측한 선행 연구의 현장자료와 비교하였으며, 파랑변형의 수치결과는 현장자료와 비교적 양호한 일치를 보였다. 해빈류의 수치결과는 연안사주가 발단된 지역에서 다소 과소평가 되었지만, 전반적으로 해빈류의 공간적 분포에 대하여 정도 있게 예측한 것으로 여겨진다.
본 연구는 최근의 연안역 개발 사업 이전에 선행되어야 하는 물리학적 변화요인들( 파랑변형과 주변해역의 해양 환경적 변화 요인 등)에 대한 연구에 그 목적이 있다. 이러한 관점에서 울산 신항과 같은 연안역에서의 DELFT-3D: WAVE(SWAN)을 이용하여 대상 해역의 파랑특성을 파악했다, 파랑특성 파악을 위해서 다방향 불규칙파의 굴절 및 천수변형을 동시에 풀 수 있는 에너지 평형 방정식을 사용한 수치모델인 SWAN 모델에 대해 연구하였다. 이러한 과정을 통해서 울산 신항 주변 해역의 불규칙 파랑특성을 파악했다. 파랑특성 파악의 가상 좋은 방법은 현장 파고계를 설치하여 장기간에 걸쳐 파랑을 직접 관찰하는 것이다. 그러나 광범위한 지역에 대한 파랑특성 파악에는 어려움이 있어서 이에 대한 대안으로 수치모텔인 DELFT-3D; WAVE를 이용해서 불규칙 파랑특성을 파악했다.
Copeland’s(1985) hyperbolic mild-slope equation including diffraction refraction and reflection in the wave field is used as a governing equation in this study. The result of Maruyama & Kajima(1985) is used to calculate wave direction and that of Watanabe & Maruyama(1986) is used as a energy dissipation formula. Numerical solutions are obtained by the Leap-Frog scheme and compared with Watanabe & Maruyama’s (1984) hydraulic experimental results and numerical simulation results for the detached breakwater. This wave model is applied to a detached breakwater and compared with Watanabe and Maruyama’s (1984) hydraulic model results to check the characteristics of reflected wave field around a detached breakwater. The distribution of wave height and we phase in front of a detached breakwater is more accurate than the Watanabe and Maruyama’s numerical results. The results from our wave model show good agreements with the others and also show nonlinear effects around the detached breakwater. This model is applied to the Gamcheon harbor of pusan. the field observations were carried out at Pusan harbor wave station in 1986-1995 and the results were accepted as a design wave condition in this study. The wave height and wave period was measured by Dong-A university at one station in the Gamcheon harbor in 1996-1997 and used as a calibration criterion. The measured data were used as input data for the numerical simulation and also compared with simulated results. The numerical simulation shows a fairly good results which considering the effect of topographic characteristics and effect of narrow entrance due to two separated breakwaters in Gamcheon harbor. The wave distribution characteristics inside Gamcheon harbor is quite different with the offshore wave direction and wave period.
Ebersole(1995)의 접근법을 사용하여 Massel(1993)의 확장형 완경사방정식에서 유도되는 eikonal 식과 파랑 에너지전송식과 또한 파수의 비회전성을 이용하여 파랑변형을 예측하였다. 완경사방정식에 무시되었으나 확장형 완경사방정식에 고려된 고차의 수심변화 효과, 즉 수심경사의 제곱 및 수심의 곡률이 고려되면 수심변화가 심한 경우에 더 정확한 해석이 될 것이라는 예측이 수치실험 결과 제대로 나타나지 않았다. 이는 수심변화가 심한 경우 eik
A theoretical formulation is performed to investigate the wave reflection and transmission ratios by a submerged multi-layered rubble-mound breakwater. This theory, which is based on the linear boundary integral method, can be extended to the multi-layered breakwater with arbitrary cross section. In the theoretical analysis evanescent mode wave is not considered, since fictitious open boundaries are put on the places far from the structure. Therefore the mathematical presentation may be simpler, and computational time shorter. The validity of obtained numerical results is demonstrated by comparing with ones of impermeable and permeable breakwaters. Comparison shows resonable agreement. On the basis of these verifications this theory is applied to the one and two-layered submerged rubble-mound breakwater with trapezoidal type.
The present paper discusses the nonlinear wave deformation due to a submerged coastal structure. Theory is based on the frequency-domain method using the third order perturbation and boundary integral method. Theoretical development to the second order perturbation and boundary integral method. Theoretical development to the second order Stokes wave for a bottom-seated submerged breakwater to the sea floor is newly expanded to the third order for a submerged coastal structure shown in Figure 1. Validity is demonstrated by comparing numerical results with the experimental ones of a rectangular air chamber structure, which has the same dimensions as that of this study. Nonlinear waves become larger and larger with wave propagation above the crown of the structure, and are transmitted to the onshore side of the structure. These characteristics are shown greatly as the increment of Ursell number on the structure. The total water profile depends largely on the phase lag among the first, second and third order component waves.