Numerical Investigation of Hydraulic Characteristics of Vertical Drops with Screens and Gradually Wall Expanding

Document Type : Research Article

Authors

1 PhD civil student in Tabriz University

2 Professor, ph.d, Faculty of Civil Engineering, University of Tabriz, Tabriz, Iran

3 Department of Civil Engineering, Faculty of Engineering, University of Maragheh, Iran.

Abstract

In the present study, the hydraulic characteristics of vertical drops with screens and the gradual wall expanding downstream using FLOW-3D software are investigated. For this purpose, two porosity ratios of the screens of 40 and 50%, 5 gradually expanding with 3 vertical drop heights in the specified discharge range were used. It was found that the numerical results are closer to the experimental results with the RNG turbulence model than k-ε. By increasing the drop height, the ΔE/E0 due to the jet floor impact intensity increased and yp/P value decreased. The maximum ΔE/E0 for 25 cm height was 51.60% and the lowest for 15 cm was 44.25%. For a constant drop height with increasing discharge, the ΔE/E0 decreased and yp/P increased. The gradually wall expanding causes turbulence on the edges and a non-uniform distribution of yd/P and by increasing yp/P and yd/P, it caused a 25% increase in ΔE/E0. The presence of screens increased yp/P, yd/P, and ΔE/E0 by 44%. The simultaneous use of gradually walls expanding and screens caused a 46% increase in ΔE/E0 and a decrease in yp/P and yd/P values. It was shown that the contribution of screens is greater than the gradually wall expanding, with their simultaneous application increasing ΔE/E0 up to 33.5%.

Keywords

Main Subjects


[1] Moore, W. L., Energy loss at the base of a free overfall. Transactions of the American Society of Civil Engineers, 1943. 108(1), p. 1343-1360.
[2] Rajaratnam, N. and M. R. Chamani, Energy Loss at Drops. Journal of Hydraulic Research, 1995. 33(3), p. 373-384.
[3] Esen, I.I., J.M. Alhumoud, and K. A. Hannan, Energy Loss at a Drop Structure with a Step at the Base. Water international, 2004. 29(4), p. 523-529.
[4] Chamani, M. R., N. Rajaratnam, and M.K. Beirami, Turbulent jet energy dissipation at vertical drops. Journal of hydraulic engineering, 2008. 134(10), p. 1532-1535.
[5] Mansouri, R., and A.N. Ziaei, Numerical modeling of the flow in the vertical drop with inverse apron. 11th International Conference on Hydroinformatics, New York City, USA, 2014.
[6] Sadeghfam, S., A.A. Akhtari, R. Daneshfaraz, and G. Tayfur, Experimental investigation of screens as energy dissipaters in submerged hydraulic jump. Turkish Journal of Engineering and Environmental Sciences, 2015. 38(2), p. 126-138.
[7] Daneshfaraz, R., S. Sadeghfam, A. Rezazadeh Joudi, Experimental investigation on the effect of screen’s location on the flow's energy dissipation. Irrigation and Drainage Structures Engineering Research, 2017. 17(67), 47-62 (in Persian). DOI:  10.22092/aridse.2017.109616
[8] Daneshfaraz, R., S. Sadeghfam, and A. Ghahramanzadeh, Three-dimensional numerical investigation of flow through screens as energy dissipators. Canadian Journal of Civil Engineering, 2017. 44(10), p. 850-859.
[9] Kabiri-Samani, A.R., E. Bakhshian, and M.R. Chamani, Flow characteristics of grid drop-type dissipators. Flow Measurement and Instrumentation, 2017. 54, p. 298-306.
[10] Daneshfaraz, R., S. Sadeghfam, A. Rezazadeh Joudi, Experimental Investigation of Energy Dissipation in the Sudden Choked Flow with Free Surfaces. Journal of Civil and Environmental Engineering, 2018. 48(2), 101-108 (in Persian).
[11] Ghaderi, A., M. Dasineh, S. Abbasi, Impact of Vertically Constricted Entrance on Hydraulic Characteristics of Vertical Drop (Numerical Investigation). Journal of Hydraulics, 2019. 13(4), p. 121-131.
[12] Daneshfaraz, R., S. Sadeghfam, and A. Tahni, Experimental Investigation of Screen as Energy Dissipators in the Movable-Bed ChannelIranian Journal of Science and Technology, Transactions of Civil Engineering, 2019. Doi: 10.1007/s40996-019-00306-7.
[13] Daneshfaraz, R., S. Sadeghfam, V. Hasanniya, Experimental investigation of energy dissipation the vertical drops equipped with a horizontal screen with the supercritical flow. Iranian Journal of Soil and Water Research, 2019. (In Persian). DOI: 10.22059/ijswr.2019.269301.668053
[14] Norouzi, R, R. Daneshfaraz, and A. Bazyar, The Study of Energy Dissipation due to the use of Vertical Screen in the Downstream of Inclined Drops by Adaptive Neuro-Fuzzy Inference System (ANFIS). AUT Journal of civil engineering. 2019.(In Persian). DOI: 10.22060/CEEJ.2019. 16694. 6305.
[15] ] Sadeghfam, S.  R. Daneshfaraz, R. Khatibi, O. Minaei, Experimental studies on scour of supercritical flow jets in upstream of screens and modelling scouring dimensions using artificial intelligence to combine multiple models (AIMM), Journal of Hydroinformatics, 2019.
[16] Hager, W.H. Hydraulic jump in non-prismatic rectangular channels. Journal of Hydraulic Research, 1985. 23(1), p. 21-35.
[17] Grant, D.M. and B.D. Dawson, Open Channel Flow Measurement Handbook". 5th ed. ISCO Inc. 1998.
[18] Çakir, P. Experimental investigation of energy dissipation through screens (Doctoral dissertation, M. Sc. thesis, Department of Civil Engineering, Middle East Technical University, Ankara, Turkey). 2003.  
[19] Balkiş, G. Experimental Investigation of Energy Dissipation through Inclined Screens. (Doctoral dissertation, Middle East Technical University, Ankara, Turkey), 2004.  
[20] Flow Science Inc. FLOW-3D V 11.2 User’s Manual. Santa Fe, NM, USA. 2016
[21] Ghaderi, A., Abbasi, S. CFD simulation of local scouring around airfoil-shaped bridge piers with and without collar. Sādhanā, 44(10), 216, 2019.
[22] Daneshfaraz, R., A. Ghahramanzadeh, A. Ghaderi, A.R. Joudi, J. Abraham, Investigation of the Effect of Edge Shape on Characteristics of Flow under Vertical Gates. Journal‐American Water Works Association, 2016. 108(8): 425-432.
[23] Daneshfaraz, R., O. Minaei, J. Abraham, S. Dadashi, A. Ghaderi, 3-D Numerical simulation of water flow over a broad-crested weir with openings. ISH Journal of Hydraulic Engineering, 2019. 1-9.
[24] Daneshfaraz, R., and Ghaderi, A. Numerical Investigation of Inverse Curvature Ogee Spillway. Civil Engineering Journal, 3(11): 1146-1156. 2017.
[25] Versteeg, H. K., and W. Malalasekera, An introduction to computational fluid dynamics: the finite volume method, Pearson Education. 2007.
[26] Ghaderi, A., Dasineh, M., Abbasi, S., and Abraham, J. Investigation of trapezoidal sharp-crested side weir discharge coefficients under subcritical flow regimes using CFD. Applied Water Science, 10(1), pp. 1-12, 2020
[27] Nayebzadeh, B., M.A. Lotfolahi-Yaghin, and R. Daneshfaraz, Experimental study of Energy Dissipation at a Vertical Drop Equipped with Vertical Screen with Gradually Expanding at the Downstream. AUT Journal of civil engineering, 2019.  (In Persian). DOI: 1022060/CEEJ.2019.16493.6265.