Factors Affecting Brink Depth in Rectangular Overfalls

  • G. C. Christodoulou
  • G. C. Noutsopoulos
  • S. A. Andreou

Abstract

The rectangular free overfall serves as a common control structure in subcritical flows, due to the presence of a critical section where a definite depth vs. discharge relationship is known to exist. In fact, due to the significant flow curvature near the brink, the brink depth, yb, is less than the critical depth, yc,computed on the basis of parallel flow for a given discharge, Q. The critical depth section is observed to lie at a distance of about 3–4 yc upstream of the brink. Since the establishment of a dependable correlation between Q and yb is essential for the practical use of the overfall as a control structure, the need for an accurate estimation of the ratio yb/yc under known flow conditions is evident.

Keywords

Crest Rounded 

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References

  1. 1.
    Andreou, S.A. (1980) Free overfall for subcritical upstream flow. Diploma Thesis, Dept. of Civil Engineering, Natl. Tech. Univ. of Athens.Google Scholar
  2. 2.
    Bauer, S.W.,and Graf, W.H. (1971) Free overfall as a flow measuring device. J. Irrigation and Drainage Div., ASCE, 97, IR1: 73–83.Google Scholar
  3. 3.
    Delleur, J.W., Dooge, J.C.I., and Gent, K.W. (1956) In- fluence of slope and roughness on the free overfall. J. Hydraulics Div., ASCE, 82, HY4, Proc. Paper 1038; 30–35.Google Scholar
  4. 4.
    Kraijenhoff, D.A., and Dommerholt, method in rectangular channel. J. Div., ASCE, 103, IR2: 171–177.Google Scholar
  5. 5.
    Markland, E. (1965). Calculation of flow at a free overfall by relaxation method. I.C.E. A. paper 6869: 71–78.Google Scholar
  6. 6.
    Rajaratnam, N., and Muralidhar, D. (1968). Characteristics J. fo the rectangular free overfall. J. Hydraulic Research,o 6, 3: 233–258.CrossRefGoogle Scholar
  7. 7.
    Replogle, J.A. (1962) Discussion, End depth at a drop in trapezoidal channels, by M.H. Diskin. J. Hydraulics Divi-sion, ASCE, 88, HY2: 161–165.Google Scholar
  8. 8.
    Rouse, H. (1936) Discharge characteristics of the free overfall. Civil Engineering, 6, 4: 257–260.Google Scholar
  9. 9.
    Smith, C.D. (1972) Discussion, Free overfall as flow mea- suring device, by S.W. Bauer and W.H. Graf, J. Irrigation and Drainage Division, ASCE, 98, IR1: 162–164.Google Scholar
  10. 10.
    Strelkoff, T.,and Moayeri, M. (1970) Pattern of potential flow in a free overfall. J. Hydraulics Division, ASCE, 96, HY4: 879–901.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1984

Authors and Affiliations

  • G. C. Christodoulou
    • 1
  • G. C. Noutsopoulos
    • 1
  • S. A. Andreou
    • 1
  1. 1.Dept. of Civil EngineeringNational Technical Univ. of AthensGreece

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