Discharge Characteristics of Triangular Weir with Upstream Ramp and Its CFD Modelling Using Ansys CFX Module

  • Subhojit KadiaEmail author
  • Binit Kumar
  • Zulfequar Ahmad
Conference paper
Part of the GeoPlanet: Earth and Planetary Sciences book series (GEPS)


To understand the flow field and discharge characteristics of a triangular weir with an upstream ramp (TW-UR), experimental study as well as computational fluid dynamics (CFD) simulation were performed. The Ansys CFX module and standard k-ε turbulent model were used in the simulation. It was observed that the TW-UR had about 9.8–14.3% higher discharging capacity than a sharp-crested weir of the same height and it was found that about 10–15% higher discharging capacity was estimated in the CFD simulation as compared to the observed data under the same head. The highly active flow field in the upstream side and enhanced velocity along the flow direction due to flow contraction in the vertical plane are helpful in enhancing the hydrodynamic force exerted by the moving fluid and creating the chances of sediment passage as well as increasing the discharging capacity. Existing two equations of the coefficient of discharge for TW-UR were checked for their accuracy using the present and previous experimental data, and it was observed that the equation proposed by Azimi et al. (J Irrig Drain Eng 139(1):75–83, 2013) predicted the coefficient of discharge within ±5, ±10 and ±15% error ranges for 43.0, 72.5 and 92.5% datasets, whereas within those error ranges, equation proposed by Di Stefano et al. (J Irrig Drain Eng 142(10):04016036-1–9, 2016) estimated the coefficient of discharge for 61.7, 92.3 and 100% datasets, respectively. Statistical analysis showed that in most of the cases, the equation of Di Stefano et al. (J Irrig Drain Eng 142(10):04016036-1–9, 2016) showed better precision than Azimi et al. (J Irrig Drain Eng 139(1):75–83, 2013) equation, and overall, the equation proposed by Di Stefano et al. (J Irrig Drain Eng 142(10):04016036-1–9, 2016) is more accurate than the equation proposed by Azimi et al. (J Irrig Drain Eng 139(1):75–83, 2013).


Discharge characteristics Triangular weir Experimentation CFD Existing equations 



The first author would like to thank WBSEDCL for sponsoring his master’s study. He would also like to express his gratitude to Prof. S. K. Mishra, WRD & M, IIT Roorkee, for his fruitful advice and encouragement. The second author is extremely thankful to the MHRD, Government of India for sponsorship.


  1. Abou-Seida MM, Quraishi AA (1976) A flow equation for submerged rectangular weirs. Proc Inst Civil Eng Part 2(61):685–696Google Scholar
  2. Acharya R (2016) Investigation of differences in Ansys solvers CFX and fluent. Master thesis, KTH Royal Institute of Technology, Stockholm, SwedenGoogle Scholar
  3. ANSYS (2018) ANSYS academic research mechanical and CFD, Release 19.1, Canonsburg, PAGoogle Scholar
  4. Aydin MC, Emiroglu ME (2013) Determination of capacity of labyrinth side weir by CFD. Flow Meas Instrum 29:1–8CrossRefGoogle Scholar
  5. Aydin MC, Emiroglu ME (2016) Numerical analysis of subcritical flow over two-cycle trapezoidal labyrinth side weir. Flow Meas Instrum 48:20–28CrossRefGoogle Scholar
  6. Azimi AH, Rajaratnam N (2009) Discharge characteristics of weirs of finite crest length. J Hydraul Eng 135(12):1081–1085CrossRefGoogle Scholar
  7. Azimi AH, Rajaratnam N, Zhu DZ (2012) A note on sharp-crested weirs and weirs of finite crest length. Can J Civ Eng 39(11):1234–1237CrossRefGoogle Scholar
  8. Azimi AH, Rajaratnam N, Zhu DZ (2013) Discharge characteristics of weirs of finite crest length with upstream and downstream ramps. J Irrig Drain Eng 139(1):75–83CrossRefGoogle Scholar
  9. Azimi H, Shabanlou S (2015) U-shaped channels along the side weir for subcritical and supercritical flow regimes. Flow Meas Instrum 46:170–178CrossRefGoogle Scholar
  10. Bai Y, Duan JG (2014) Simulating unsteady flow and sediment transport in vegetated channel network. J Hydrol 515:90–102CrossRefGoogle Scholar
  11. Bates PD, Lane SN, Ferguson RI (2005) Computational fluid dynamics: applications in environmental hydraulics. John Wiley & Sons Ltd, ChichesterCrossRefGoogle Scholar
  12. Berggren M, Ekström SE, Nordström J (2009) A discontinuous Galerkin extension of the vertex-centered edge-based finite volume method. Commun Comput Phys 5(2–4):456–468MathSciNetzbMATHGoogle Scholar
  13. Bremer F, Oertel M (2017) Numerical investigation of wall thickness influence on Piano Key Weir discharge coefficients: a preliminary study. In: Proc. of the third international workshop on labyrinth and Piano Key Weirs 2017, Taylor & Francis Group, London, pp 101–108Google Scholar
  14. Crookston BM, Anderson RM, Tullis BP (2018) Free-flow discharge estimation method for Piano Key Weir geometries. J Hydro-Environ Res 19:160–167CrossRefGoogle Scholar
  15. Di Stefano C, Ferro V, Bijankhan M (2016) New theoretical solution of the outflow process for a weir with complex shape. J Irrig Drain Eng 142(10):04016036-1–9Google Scholar
  16. Fan J, Morris GL (1992) Reservoir sedimentation. I: delta and density current deposits. J Hydraul Eng 118(3):354–369CrossRefGoogle Scholar
  17. Garde RJ, Ranga Raju KG (2015) Mechanics of sediment transportation and alluvial stream problems. Revised 3rd edn. New Age International (P) Ltd., New DelhiGoogle Scholar
  18. Henderson FM (1966) Open channel flow. Macmillan, New YorkGoogle Scholar
  19. Horton RE (1907) Weir experiments, coefficients, and formulas. In: Proc. U.S. geological survey—water supply and irrigation (200), Government Printing office, Washington, DCGoogle Scholar
  20. Hoseini SH, Jahromi SHM, Vahid MSR (2013) Determination of discharge coefficient of rectangular broad-crested side weir in trapezoidal channel by CFD. Int J Hydraul Eng 2(4):64–70Google Scholar
  21. Hu H, Qian Z, Yang W, Hou D, Du L (2018) Numerical study of characteristics and discharge capacity of Piano Key Weirs. Flow Meas Instrum 62:27–32CrossRefGoogle Scholar
  22. Kabiri-Samani A, Javaheri A (2012) Discharge coefficients for free and submerged flow over Piano Key Weirs. J Hydraul Res 50(1):114–120CrossRefGoogle Scholar
  23. Kim S, Im J, Lee SO (2014) Assessment of sediment exclusion efficiency for several modified labyrinth weirs. Paddy Water Environ 12(Supp. 1):133–140CrossRefGoogle Scholar
  24. Kumar S, Ahmad Z, Mansoor T (2011) A new approach to improve the discharging capacity of sharp-crested triangular plan form weirs. Flow Meas Instrum 22:175–180CrossRefGoogle Scholar
  25. Launder BE, Spalding DB (1972) Lectures in mathematical models of turbulence. Academic Press, London, New YorkzbMATHGoogle Scholar
  26. Launder BE, Spalding DB (1974) The numerical computation of turbulent flows. Comput Methods Appl Mech Eng 3:269–289ADSCrossRefGoogle Scholar
  27. Shaker AJ, Sarhan AS (2017) Performance of flow over a Weir with sloped upstream face. ZANCO J Pure Appl Sci 29(3):43–54Google Scholar
  28. Tiwari H, Sharma N (2017) Turbulence study in the vicinity of Piano Key Weir: relevance, instrumentation, parameters and methods. Appl Water Sci 7:525–534ADSCrossRefGoogle Scholar

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© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Department of WRD & MIndian Institute of Technology RoorkeeRoorkeeIndia
  2. 2.Department of Civil EngineeringIndian Institute of Technology RoorkeeRoorkeeIndia

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