Figure 5. Flow field, eddies and dead zones in S1 and S2 simulations
Figure 5. Flow field, eddies and dead zones in S1 and S2 simulations
Figure 5. Flow field, eddies and dead zones in S1 and S2 simulations

Groynes 주변의 지형 및 수리학적 수치 시뮬레이션

연구 배경 및 목적

문제 정의

  • 하천 및 하구에서 발생하는 침식 문제를 해결하기 위해 Groynes(제방 구조물)이 널리 사용됨.
  • Groynes 주변의 흐름과 침식 현상을 정확히 이해하는 것은 수로 보호 및 유지관리에 필수적임.
  • 실험적 연구는 시간과 비용이 많이 소요되므로 컴퓨터 기반 CFD(전산유체역학) 시뮬레이션을 활용하여 수리학적 특성을 분석하는 연구가 필요함.

연구 목적

  • FLOW-3D를 이용하여 Groynes 주변의 유동 및 세굴(scour) 현상을 수치적으로 분석.
  • 실험 결과와 비교하여 FLOW-3D 모델의 정확성을 검증.
  • SSIIM 2.0 소프트웨어와의 비교 분석을 통해 다양한 모델의 예측 정확도 평가.

연구 방법

FLOW-3D 모델링 및 시뮬레이션 설정

  • VOF(Volume of Fluid) 기법을 사용하여 자유 수면을 추적.
  • RNG k-ε 난류 모델을 적용하여 난류 흐름을 해석.
  • 지형 모델링: Soulsby-Whitehouse 방정식을 이용하여 세굴 예측.
  • 경계 조건:
    • 유입: Froude 수 기반의 흐름 조건 적용.
    • 유출: 자연 배출 경계 조건 설정.
    • 바닥: 이동 가능한 퇴적층으로 설정.

주요 결과

유동 및 세굴 특성 분석

  • Groynes 주변에서 강한 와류(vortex) 발생 → 세굴 형성에 주요 원인.
  • Froude 수가 낮을수록 모델 예측 정확도 향상.
  • SSIIM 2.0 대비 FLOW-3D가 보다 정확한 흐름 및 세굴 패턴 예측.
  • 실험 결과와 비교 시 최대 세굴 깊이 차이가 10% 이내로 나타남.

결론 및 향후 연구

결론

  • FLOW-3D를 활용한 수치 시뮬레이션이 실험 결과와 높은 일치도를 보이며, Groynes 주변의 유동 및 세굴 현상을 효과적으로 예측 가능.
  • Froude 수와 유속 비(Uavg/Ucr)에 따라 모델 정확도가 달라지며, 추가적인 실험 검증이 필요.

향후 연구 방향

  • LES(Large Eddy Simulation)와 같은 고급 난류 모델 적용을 통한 예측 정확도 향상.
  • 다양한 하천 형상 및 유량 조건에서 추가적인 검증 수행.
  • 실제 하천 데이터와의 비교를 통한 모델 보정.

연구의 의의

이 연구는 FLOW-3D를 활용하여 Groynes 주변의 유동 및 세굴 현상을 정량적으로 분석하고, 수치 모델의 정확성을 실험적으로 검증하였다. 하천 관리 및 구조물 설계의 최적화에 기여할 수 있는 데이터와 분석 방법을 제공한다.

Figure 5. Flow field, eddies and dead zones in S1 and S2 simulations
Figure 5. Flow field, eddies and dead zones in S1 and S2 simulations
Figure 6. Morphology bed changes in S1 (a) laboratory experiments and (b) FLOW-3D simulation
Figure 6. Morphology bed changes in S1 (a) laboratory experiments and (b) FLOW-3D simulation
Figure 7. Morphology bed changes in S2 (a) laboratory experiments and (b) FLOW-3D simulation
Figure 7. Morphology bed changes in S2 (a) laboratory experiments and (b) FLOW-3D simulation

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