Skip to main content
Log in

Numerical Study of Discharge-Head Relationship of Piano Key Weirs for Low Heads

  • HYDROPHYSICAL PROCESSES
  • Published:
Water Resources Aims and scope Submit manuscript

Abstract

Piano Key Weirs (PKW) is a free-flowing weir, and an improvement over the labyrinth weir family. PKW has higher discharge for the same head as compared to other types of weirs. They tend to reduce the upstream submergence in reservoirs or other flow systems and can be effectively used for flood risk mitigation. CFD studies have been carried out earlier but mostly for H/P (Total head to height ratio) greater than 0.1. The present paper investigates the use and validation of Computational Fluid Dynamics (CFD) for modeling Open Channel flows over common hydraulic structures such as PKW for small discharges with the entire range of head to height ratio h/P from 0.035 to 0.1, where h is not the total head upstream of PKW but the head measured at the crest of PKW. The numerical results have been validated with experimental results. Since the discharge is minimal surface tension force has been incorporated in the numerical model. The numerical model is a half PKW unit model with the same geometrical parameters as the experimental setup from Literature. The results show that CFD simulations can reproduce flow depths near PKW with reasonably good accuracy. The present paper compares the head obtained from CFD with that of empirical formula in the Literature but with head measured at the crest of PKW. Investigation of water surface profile and velocity profile near the upstream of PKW has also been carried out.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.

Similar content being viewed by others

REFERENCES

  1. Abrari, L., Talebbeydokhti, N., and Sahraei, S., Investigation of hydraulic performance of piano shaped weirs using three dimensional numerical modeling, Iran. J. Sci. Technol., 2015, vol. 39(C2+), pp. 539–558. https://doi.org/10.22099/IJSTC.2015.3519

  2. Anderson, R. and Tullis, B., Piano key weir: Reservoir versus channel application, ASCE J. Irrig. Drain. Div., 2012, vol. 138, no. 8, pp. 773–776.

    Article  Google Scholar 

  3. Anderson, R.M., Piano Key Weir Head Discharge Relationships, Utah State University, 2011.

    Google Scholar 

  4. Bashiri, H., et al., Towards a new design equation for piano key weirs discharge capacity, Int. sympos. Hydraulic Structures, Utah State Univ., 2016. https://doi.org/10.15142/T3310628160853

    Book  Google Scholar 

  5. Bieri, M., et al. Réhabilitation de la capacité d’évacuation des crues–Intégration de PK-Weirs sur des barrages existants, Proc., Colloque CFBR-SHF, Dimensionnement et fonctionnement des évacuateurs de crues, Société Hydrotechnique de France (SHF) Paris, 2009.

  6. Carrillo, J.M., Matos, J., and Lopes, R., Numerical modeling of free and submerged labyrinth weir flow for a large sidewall angle, Environ. Fluid Mech., 2019, pp. 1–18.

  7. Eng, B.M. and Lennart, F., Numerical uncertainty of Piano Key Weir discharge coefficient estimations by means of 3D CFD modelling-a preliminary study, Int. sympos. Hydraulic Structures, Utah State Univ., 2018.

    Google Scholar 

  8. Erpicum, S., et al., Numerical and physical hydraulic modelling of Piano Key Weirs, Proc. 4th Int. Conf. on Water Resources and Renewable Energy Development in Asia, 2012.

  9. Fleit, G., Baranya, S., and Bihs, H., CFD modeling of varied flow conditions over an ogee-weir, Periodica Polytechnica-Civil Engineering, 2017.

  10. Haun, S., Olsen, N.R.B., and Feurich, R., Numerical modeling of flow over trapezoidal broad-crested weir, Engineering Applications of Computational Fluid Mechanics, 2011, vol. 5, no. 3, pp. 397–405. https://doi.org/10.1080/19942060.2011.11015381

    Article  Google Scholar 

  11. Hu, H., et al., Numerical study of characteristics and discharge capacity of piano key weirs, Flow Measurement and Instrumentation, 2018, vol. 62, pp. 27–32. https://doi.org/10.1016/j.flowmeasinst.2018.05.004

    Article  Google Scholar 

  12. Kabiri-Samani, A. and Javaheri, A., Discharge coefficients for free and submerged flow over Piano Key weirs, J. Hydraulic Res., 2012, vol. 50, no. 1, pp. 114–120. https://doi.org/10.1080/00221686.2011.647888

    Article  Google Scholar 

  13. Laugier, F., Design and construction of the first Piano Key Weir spillway at Goulours dam, Int. J. Hydrop. Dams, 2007, vol. 14, no. 5, pp. 94.

    Google Scholar 

  14. Leite Ribeiro, M., et al., Discharge capacity of piano key weirs, J. Hydraul. Eng., 2011, vol. 138, no. 2, pp. 199–203. https://doi.org/10.1061/(ASCE)HY.1943-7900.0000490

    Article  Google Scholar 

  15. Lempérière, F. and Ouamane, A., The Piano Keys weir: a new cost-effective solution for spillways, Int. J. Hydrop. Dams, 2003, vol. 10, no. 5, pp. 144–149.

    Google Scholar 

  16. Lempérière, F. and Vigny, J., General comments on labyrinth and Piano Keys Weirs–The future, Labyrinth and piano key weirs–PKW 2011, 2011, pp. 289–294.

  17. Machiels, O., et al. Large scale experimental study of piano key weirs, Proc. 33rd IAHR Congress: Water Engineering for a Sustainable Environ., IAHR, 2009.

  18. Muslu, Y., Numerical analysis for lateral weir flow, J. Irrig. Drainage Eng., 2001, vol. 127, no. 4, pp. 246–253. https://doi.org/10.1061/(ASCE)0733-9437(2001)127:4(246)

    Article  Google Scholar 

  19. Oertel, M., Discharge Coefficients of Piano Key Weirs from Experimental and Numerical Models, E-proc. 36th IAHR World Congress, 2015.

  20. Ouamane, A., Nine years of study of the Piano Key Weir in the university laboratory of Biskra “lessons and reflections,” Proc. Int. Conf. Labyrinth Piano Key Weirs-PKW 2011, London: Taylor & Francis, 2011.

  21. Ouamane, A. and Lempérière, F., Design of a new economic shape of weir, Proc. Int. Sympos. Dams in the Societies of the 21st Century, 2006.

  22. Pralong, J., et al., A naming convention for the piano key weirs geometrical parameters, Labyrinth and Piano Key Weirs, 2011, pp. 271–278.

    Book  Google Scholar 

  23. Qu, J., et al., Numerical simulation of sharp-crested weir flows, Can. J. Civ. Eng., 2009, vol. 36, no. 9, pp. 1530–1534. https://doi.org/10.1139/L09-067

    Article  Google Scholar 

  24. Ribeiro, M., et al., Rehabilitation of St-Marc dam. Experimental optimization of a piano key weir, Proc. of the 32nd Congress of IAHR, 2007.

  25. Ribeiro, M.L., et al., Hydraulic design of A-type piano key weirs, J. Hydraulic Res., 2012, vol. 50, no. 4, pp. 400–408. https://doi.org/10.1080/00221686.2012.695041

    Article  Google Scholar 

  26. Sharma, N. and Tiwari, H., Experimental study on vertical velocity and submergence depth near Piano Key Weir, Labyrinth and Piano Key Weirs II-PKW, 2013, pp. 93–100.

    Book  Google Scholar 

  27. Tiwari, H. and Sharma, N., Empirical and Mathematical Modeling of Head and Discharge over Piano Key Weir, Development of Water Resour. India, Springer, 2017, pp. 341–354.

    Google Scholar 

Download references

ACKNOWLEDGMENTS

We acknowledge IIT (BHU), Varanasi for infrastructure support as well as Main Library IIT (BHU), Varanasi, for paper downloads.

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Amiya Abhash or K. K. Pandey.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Abhash, A., Pandey, K.K. Numerical Study of Discharge-Head Relationship of Piano Key Weirs for Low Heads. Water Resour 48, 235–244 (2021). https://doi.org/10.1134/S0097807821020020

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S0097807821020020

Keywords:

Navigation