Experimental Study of Discharge Coefficient of Combination Labyrinth Weirs

Document Type : Research Paper

Authors

Department of Water Science & Engineering, Arak University, Arak city, Iran.

Abstract

Labyrinth weirs are one of the kind of nonlinear crest weirs causing the increase of discharge capacity for specified height of water level in canals and dams. In this study, the effects of dentate and orifice labyrinth weirs on increasing the discharge capacity were investigated. Experiments were conducted in a laboratory flume with length of 12 m and width of 0.8 m. The nine experimental models with 15 cm height were used. The results showed that for L/W=2 and H/P=0.2, the discharge coefficient of the orifice-dentate labyrinth weir and the dentate labyrinth weir are 75.6% and 17.5%, more than the simple labyrinth weir, respectively. However, dent and orifice may decrease their efficiency in high heads and the discharge coefficient will be close to simple labyrinth weir. The reason for these changes was increasing the flow interference in downstream of labyrinth weir between dents, orifices and weir with increasing discharge. Also, the result showed the efficiency of orifice and dentate on labyrinth weirs will decrease with increasing the weir magnification (L/W) and they lose their effect.

Keywords

References

  1. Ahmadi Z, Mohseni Movahed S and Mozaffari J (2019). The effects of dentate crest and a row of consecutive orifices along and below the crest edge on labyrinth weir efficiency. Canadian of journal of civil engineering, 46: 552–555.
  2. Bahreh Bar A R, Heidarnejad M, Masjedi A R and Bordbar A (2021). Numerical and Experimental Study of the Combination of Labyrinth Weir with Orifice and its Effect on Discharge Coefficient. Journal of Water and Soil Science, 25(2): 91-105.
  3. Christensen N (2012). Flow Characteristics of Arced Labyrinth Weirs, Utah State University, Logan, Utah.
  4. Dabling M, Tullis B (2018). Labyrinth weirs with angled approach flow. Journal of hydraulic engineering, 144(12).
  5. Emiroglu M, Kaya N and Agaccioglu H (2010). Discharge capacity of labyrinth side spillways located on a straight channel. Journal of irrigation and drainage engineering, 136(1), 37-46.
  6. Ghaderi A, Daneshfaraz R, Dasineh M and Di Francesco S (2020). Energy dissipation and hydraulics of flow over trapezoidal–triangular labyrinth weirs. Water Journal, 12(7): 1-18.
  7. Hay N, Taylor G (1970). Performance and design of labyrinth weirs. American Society of Civil Engineering. Journal of Hydraulic Engineering, 96: 2337-2357.
  8. Lux F L and Hinchliff D (1985). Design and Construction of Labyrinth Spillway.15th International Congress on Large Dam, International commission on Large Dams, Paris, France, 249-274.
  9. Meshkavati J, Emadi A R, Dehghani A H and Msoudian M (2017). Experimentally investigation of discharge coefficient at trapezoidal labyrinth weirs. Iranian Journal of Irrigation and Drainage, 11(5):852-864.
  10. Seo I W, Do Kim Y, Park Y S and Song C G (2016). Spillway discharges by modification of weir shapes and overflow surroundings. Environmental Earth Sciences, 75(6): 1-13.
  11. Tullis B P, Amanian N, and Waldron D (1995). Design of labyrinth weir spillways. American Society of Civil Engineering. Journal of Hydraulic Engineering, 121(3): 247-255.
  12. Tullis B P, Crookston B M (2012). Labyrinth weirs. Nappe interference and local submergence. Journal of irrigation and drainage, 138(8), 757-765.

Files

Share

How to cite

Statistics