Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
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Effect of Corrected Hydrostatic Pressure in Shallow-Water Flow over Large Slope

대경사를 지나는 천수 흐름에서 수정된 정수압의 효과

  • 황승용 (한국건설기술연구원 수자원.환경연구본부 하천해안연구실)
  • Received : 2014.11.03
  • Accepted : 2014.11.10
  • Published : 2014.12.31
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Abstract

This study suggests a new hydrostatic pressure distribution corrected for nonuniform flow over a channel of large slope. For analyzing shallow-water flows over large slope accurately, it is developed a finite-volume model incorporating the pressure distribution to the shallow water equations. Traveling speed of the hydraulic jump downstream a parabolic bump in the drain case is quite reduced by the weakened bottom gradient source term in the model with the pressure correction. In simulating the dam-break flow over a triangular sill, it is identified that the model with pressure correction could capture the water surface by the digital imaging measurements more than the model without that. Due to the pressure correction decreasing the reflected flows on and increasing overflows over the sill, there are good agreements in the experiment and the simulation with that. Therefore, this model is expected to be applied to such practical problems as flows in the spillway of dam or run-up on the beach.

대경사 수로의 부등류에 대해 적용될 수 있도록 수정된, 새로운 정수압 분포를 제시하였다. 이것을 천수방정식에 적용하여 대경사를 지나는 천수 흐름을 정확하게 해석할 수 있는 유한체적 모형을 개발하였다. 포물선형 융기의 배수에 대해 압력 수정이 고려된 모형에서 바닥 경사 생성항의 영향이 줄어들어 융기의 하류에서 도수의 진행 속도가 크게 감소되었다. 삼각형 턱을 지나는 댐 붕괴 흐름에 대한 모의에서 압력 수정항이 추가된 모형으로 디지털 영상분석에 의한 수면을 압력 수정이 고려되지 않은 경우에 비해 더 잘 포착할 수 있음을 확인하였다. 압력 수정항 덕분에, 턱에 반사되는 흐름은 줄어들고 월류는 늘어 모의 결과가 실험 결과에 잘 부합된다. 따라서 댐의 여수로나 해안의 처오름 등 실용적인 문제에 대한 이 모형의 적용성이 기대된다.

Keywords

References

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