Discharge Coefficient in Vertical Intakes with Additional Plates

Document Type: Research Paper

Authors

Department of Water Science Engineering, Agriculture Faculty, Tabriz University, Tabriz,Iran.

Abstract

One of the causes of perturbation at vertical intakes is the happening of vortices with an air core. The vortices with an air core occur whenever the submergence of the intake is less than a critical value. Anti-vortex devices and specially plates are used to avoid the negative effects of the air-core vortices. If plates are used, then the geometry of them should be studied experimentally. Accordingly, a precise set of experiments have been carried out using rectangular plates with different dimensions. The results showed that using the vertical plates can increase the critical submergence for the same discharge rates to 51%.

Keywords


  1. Hecker GE (1987). Fundamentals of vortex intake flow. Swirling flow problems at intakes. IHAR Hydraulic structures design manual 1, J. Knauss Ed. Balkema, Rotterdam, The Netherlands, pp.13-38.
  2. Rindels AJ and Gulliver JS (1983). An experimental study of critical submergence to avoid free-surface vortices at vertical intakes. Saint Anthony Fall Hydraulic Laboratory. Project Report No. 224.
  3. Yildirim N and Kocabas F (1995). Critical submergence for intakes in open channel flow. Journal of Hydraulic Engineering, ASCE, 121(12): 900-905.
  4. Yildirim, N. and Kocabas, F., Prediction of critical submergence for an intake pipe [J]. J. Hyd. Res., IHAR, 2002, 121(12): 900-905.
  5. Yildirim, N., Critical submergence for rectangular intake [J]. J. Engrg. Mech., ACSE, 2004, 130(10): 1195-1210.
  6. Yildirim, N., Kocabas, F. and Gulcan, S.C. Flow boundary effects on critical submergence of intake pipe [J]. J. Hyd. Engrg., ASCE, 2000, 126(4): 288-297.
  7. Yildirim, N., Kocabas, F. and Gulcan, S.C. Errata for flow boundary effects on critical submergence of intake pipe [J]. J. Hyd. Engrg., ASCE, 2007, 133(4): 463-472.
  8. Yildirim, N. and Tastan, K. Comparison of Flow-Boundary Effects on Critical Submergence of an Intake [J]. Journal of Teknik Dergi, Turkey, 2009, 20(3): 4779-4792.
  9. Tastan, K. and Yildirim, N. Effect of dimensionless parameters on air-entraining vortices. [J]. J. Hyd. Res., 2010, 48(1): 57-64.
  10. Eroglu, N. and Bahadirli, T., Prediction of critical submergence for a rectangular [J]. J. Energy. Engrg, ASCE, 2007, 133(2): 91-103.
  11. Rahimzadeh, H., Fathi, N. and Asoodeh, M.H., An experimental model of flow surface patterns at vertical downward intake with numerical validation, Int. Conf. on water resources, Hydraulics & Hydrology. Chalkida, Greece, May 11-13, 2006, pp:111-118.
  12. Li, H. and Chen, H. Experimental and numerical investigation of free surface vortex [J]. Journal of Hydrodynamics, 2008, 20(4): 481-491.
  13. Zhao, Y. et al. Numerical analysis of structure and evolution of free water vortex [J]. Journal of Xi’an Jiaotong University, 2003, 33(3): 85-88.
  14. Chen, Y., Wu, C. and Ye, M., hydraulic characteristics of vertical vortex at.
  15. Journal of Hydrodynamics, 2007, 19(2): 143-149.
  16. Sohn C. H., Ju N. G. and Gowda B. H. L., PIV study of vortexing during draining from square tanks [J]. Journal of mechanical science and technology, 2010, 24(4): 951-960.
  17. Sohn C. H., Ju N. G. and Gowda B. H. L. Draining from cylindrical tanks with vane-type suppressors, a PIV study [J]. Journal of Visualization, 2009, 12(4): 347-360.
  18. Mahyari M. N., Karimi H., Naseh H. and Mirshams M. Numerical and experimental investigation of vortex breaker effectiveness on improvement in launch vehicle ballistic parameters [J]. Journal of Mechanical Science and Technology, 2010, 24(10): 1997-2006.
  19. Sarkardeh, H., Zarrati, A.R., Jabbari, E. and Roshan, R., Discussion of prediction of intake vortex risk by Nearest Neighbor Modeling [J]. Journal of Hydraulic Engineering, 2012, 137(6): 701-705.
  20. Tagvaei, S.M., Roshan, R., Safavi, Kh. And Sarkardeh, H., Anti-vortex structures at hydropower dams [J]. International Journal of the Physical Science, 2012, 7(28): 5069-5077.
  21. Daggett LL and Keulegan GH (1974). Similitude conditions in free-surface vortex formation. Journal of Hydraulic Engineering, ASCE, 100(11):1565-1580.
  22. Anwar HO, Weller JA and Amphlett MB (1978). Similarity of free-vortex at horizontal intake. Journal of Hydraulic Research, 16(2):95-105.
  23. Jain AK, Ranga Raju KG and Garde RJ (1978). Vortex formation at vertical pipe intakes. Journal of Hydraulic Engineering, ASCE, 104(10):1429-1445.
  24. Odgaard AJ (1986). Free-surface air core vortex. Journal of Hydraulic Engineering, ASCE, 112(7): 610-620.