Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
권호 표지
DOI QR코드

DOI QR Code

The estimation of river discharge by using the mean velocity equation in a unsteady condition

평균유속공식을 이용한 부정류 하천유량 산정

  • Choo, Tai Ho (Dept. of Environmental and civil Engineering, Pusan National University) ;
  • Chae, Soo Kwon (Dept. of Environmental Health and Safety, Eulji University) ;
  • Yoon, Hyeon Cheol (Dept. of Environmental and civil Engineering, Pusan National University) ;
  • Yun, Gwan Seon (Dept. of Environmental and civil Engineering, Pusan National University)
  • 추태호 (부산대학교 사회환경시스템공학부) ;
  • 채수권 (을지대학교 보건환경안전학과) ;
  • 윤현철 (부산대학교 사회환경시스템공학부) ;
  • 윤관선 (부산대학교 사회환경시스템공학부)
  • Received : 2013.10.28
  • Accepted : 2013.12.05
  • Published : 2013.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

As the average indicator for amount of water flowing in any cross section of a river, the mean discharge has been reported to be a very important factor for examining water circle constructions in a river basin, the design and construction of a hydraulic structure, and water front area use and management. The stage-discharge curve based on discharge and stage data measured in a normal season were basically derived. Using this derivation, the necessary discharge data was obtained. The values produced in this manner corresponded to the measured data in a uniform flow state well, but showed limited accuracy in a flood season (unsteady flow). In the present paper, the mean velocity in unsteady flow conditions, which exhibited loop form properties, was estimated using the new mean velocity formula derived from Chiu's 2-D velocity. The results of RMSE and Polar graph analyses showed that the proposed equation exhibited approximately nineteen times the accuracy compared to the Manning and Chezy equations.

본 평균유량은 하천의 임의 한 단면에 흐르는 물의 양을 평균적으로 나타내는 지표로서 하천유역의 물 순환구조 파악, 하천시설의 설치, 각종 수공구조물 설계, 친수 공간 이용 및 관리 등을 목적으로 매우 중요하다. 기본적으로 평수기에 측정된 유량 및 수위자료를 바탕으로 수위-유량 관계곡선을 만들어 필요한 유량을 생산하고 있다. 이 방법은 등류상태에서는 잘 일치하나 홍수기 부정류 상태에서는 그 한계성을 보이고 있다. 따라서, 본 논문에서는 Chiu의 2차원 유속공식으로부터 유도된 새로운 평균유속 공식을 사용 하여 루프형 특성을 보이는 부정류 상황에서의 평균유속 산정을 하였다. RMSE 및 폴라그래프 분석 결과 제안된 공식은 기존의 공식들과 비교하여 약 19배 정도의 정확성을 나타내었다.

Keywords

References

  1. Chezy, A. "Developed and verified by experiments made on earthen channel", the Courpalet Canal, and on the Seine river, 1769.
  2. Chiu, C.-L., "Three-dimensional open channel flow", J Hydra Divi ASCE, Vol. 104, No. 8, pp. 1119-1136, 1978.
  3. Chiu, C.-L., "Entropy and probability concepts in Hydraulics", J Hydra Engine ASCE, Vol. 113, No. 5, pp. 583-599, 1987. DOI: http://dx.doi.org/10.1061/(ASCE)0733-9429(1987)113:5(583)
  4. Chiu, C.-L., "Entropy and 2-D velocity distribution in open channels", J Hydra Engine ASCE, Vol. 114, No. 10, pp. 738-756, 1988. DOI: http://dx.doi.org/10.1061/(ASCE)0733-9429(1988)114:7(738)
  5. Chiu, C.-L., Chen, Y.-C., "An efficient method of discharge measurement in tidal streams", J Hydro Vol. 265, pp. 212-224, 2002. DOI: http://dx.doi.org/10.1016/S0022-1694(02)00100-2
  6. Chiu, C.-L., Tung, N. C., "Maximum and regularities in open-channel flow", J Hydra Engine ASCE, Vol. 128, No. 4, pp. 390-398, 2002. DOI: http://dx.doi.org/10.1061/(ASCE)0733-9429(2002)128:4(390)
  7. Choo, T. H., "Velocity measuring method using the concept of entropy (II) - focusing on maximum velocity", J Korean Society of Civil Engineers, Vol. 22, No. 4B pp. 495-515, 2002.
  8. Choo, T. H., Yoon, H. C., Lee, S. J., "An estimation of discharge using mean velocity derived through Chiu's velocity equation", Eavironmental Earth Science, Vol. 69, pp. 247-256, 2013. DOI: http://dx.doi.org/10.1007/s12665-012-1952-0
  9. Manning, R., "On the flow of water in open channels and pipes", Transactions, Institution of Civil Engineers of Ireland Vol. 24, pp. 179-207, 1895.
  10. Xia, R., "Relation between mean and maximum velocities in a natural river." J. Hydraul. Eng., Vol. 123, No. 8, pp. 720-723, 1997. DOI: http://dx.doi.org/10.1061/(ASCE)0733-9429(1997)123:8(720)
  11. Song, T., "Velocity and turbumence distribution in non-uniform and unsteady open-channel flow", Ph. D. Dissertation, Dept. of Civil Engineering, Federal Institute of Technology Lausanne, EPFL, 1994.