Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
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Numerical simulation of submerged jump and washed-out jump using the k-𝜔 SST model

k-𝜔 SST 모형을 이용한 수중도수와 잠긴흐름의 수치모의

  • Choi, Seongwook (Department of Civil and Environmental Engineering, Yonsei University) ;
  • Choi, Sung-Uk (Department of Civil and Environmental Engineering, Yonsei University)
  • 최성욱 (연세대학교 건설환경공학과) ;
  • 최성욱 (연세대학교 건설환경공학과)
  • Received : 2021.09.29
  • Accepted : 2021.11.19
  • Published : 2021.11.30
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Abstract

This study presents numerical simulations of submerged jump and washed-out jump resulted from the flow over the embankment type weir. Unsteady Reynolds Averaged Navier-Stokes (URANS) equations are solved with the k-𝜔 SST turbulence model. Validations are carried out using the experimental results in the literature, revealing that computed roller shape, free surface, and mean velocity are in good agreement with measured data. The volume fractions of water of the submerged jump and washed-out jump are compared, and the characteristics of the two flows from the double-averaged volume fractions of water are presented. The condition under which the transition occurs from the submerged jump to washed-out jump is presented by the relation between the relative embankment length and submergence factor via numerical simulations by changing the weir length, discharge, and tailwater depth.

본 연구에서는 제방 형태의 보를 월류하는 수중도수와 잠긴흐름을 수치모의 하였다. 수치모의를 위하여 URANS 방정식을 해석하였으며, 난류폐합식으로 k-𝜔 모형을 사용하였다. 기존의 실험결과를 이용하여 수치모형을 검증하였는데, 모의된 롤러의 형상, 자유수면, 그리고 평균유속분포가 실험결과와 비교적 잘 일치하는 것을 확인하였다. 수중도수와 잠긴흐름에서 물의 체적비 분포를 비교하였으며, 각 흐름에 대한 2중 평균된 체적비의 특성을 제시하였다. 수치모의를 이용하여 보의 길이, 유량, 그리고 하류 수위에 따라 수중도수에서 잠긴흐름으로 천이되는 조건을 검토하였으며, 천이가 발생할 때의 상대 월류수심을 침수비의 함수로 제시하였다.

Keywords

Acknowledgement

본 연구는 2021년도 정부의 재원으로 한국연구재단의 지원(NRF2020R1A2B5B01098937)을 받아 수행된 연구입니다. 이에 감사드립니다.

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