Evaluation of Flow behavior over Broad-Crested Weirs of a Triangular Cross-Section using CFD Techniques
Abstract
Weirs are
barriers placed across a river and designed to control the flowing water in
order to prevent floods, make waterways operable for inland navigation and
measure flow discharge. Although there are many types of weirs, mainly used
ones are sharp-crested, circular-crested (cylindrical), broad crested and ogee
weirs. In the present study, triangular broad-crested weirs are numerically
investigated under different flow conditions. Different interior angles of 90o,
100o, 110o and 120o are included for the
opening of weirs. The flowing water over weirs is simulated using CFD
techniques and evaluated at different flow regimes with inlet discharges of
0.012 m3 s-1, 0.036 m3 s-1and 0.06
m3 s-1. The simulation results have shown that the water
level upstream the weir is inversely proportional to the opening angle, where
an increment of 10o in the opening angle leads to a drop in water
level about 1.5 cm. In addition, applying a discharge of 0.012 m3 s-1,
an uncovered region with water is created downstream the triangular broad-crested
weirs, while the bed downstream of the rectangular broad-crested weir is
covered with a thin layer of water at the same flow discharge. The
aforementioned results are compared with a comparative data and show good
agreement. By using triangular broad-crested weirs, it is important to measure
the wake region and the hitting point of falling water downstream the weirs
where this area must be strengthened well in order to resist water power and
reduce the risk of drift.
Keywords
References
- Afshar H. & Hooman H., (2013). Experimental and 3-D numerical simulation of flow over a rectangular broad-crested weir. International Journal of Engineering and Advanced Technology, 2, 6, pp. 214-219. Almohammadi, K., Ingham, D., Ma, L. & Pourkashan, M. (2013). Computational Fluid Dynamics (CFD) Mesh Independency Techniques for a Straight Blade Vertical Axis Wind Turbine. Energy, 58, 483–493. ANSYS user's guide Hoseini, S. H. Jahromi, S. H. M. & Vahid, M. S. R. (2013). Determination of Discharge Coefficient of Rectangular Broad-Crested Side Weir in Trapezoidal Channel by CFD. International Journal of Hydraulic Engineering, 2(4), 64-70. DOI: 10.5923/j.ijhe.20130204.02 Lodomez, M., Erpicum, S., Dewals, B., Pirotton, M. & Archambeau, P. (2014). Comparison between Experimental and SPH Models over a Sharp-crested Weir. The 5th International Junior Researcher and Engineer Workshop on Hydraulic Structures. Spa, Belgium. Naghavi, B., Esmaili, K., Yazdi, J, & Vahid, F.K. 2011. An experimental and numerical study on hydraulic characteristics and theoretical equations of circular weirs. Canadian Journal of Civil Engineering, 38(12): 1327–1334. doi: 10.1139/l11-092. Namaee, M. R. (2014). Numerical Investigation of a Side Weir with an Inclined Ramp. World Applied Sciences Journal, 31 (10): 1759-1766, 2014, DOI: 10.5829/idosi.wasj.2014.31.10.429 Yuce, M. I., AL-DABBAGH, M. A. & AL-BABELY, A. H. (2015). Flow simulation over oblique cylindrical weirs. Can. J. Civ. Eng., 42, 389–407. dx.doi.org/10.1139/cjce-2014-0157
Abstract
References
- Afshar H. & Hooman H., (2013). Experimental and 3-D numerical simulation of flow over a rectangular broad-crested weir. International Journal of Engineering and Advanced Technology, 2, 6, pp. 214-219. Almohammadi, K., Ingham, D., Ma, L. & Pourkashan, M. (2013). Computational Fluid Dynamics (CFD) Mesh Independency Techniques for a Straight Blade Vertical Axis Wind Turbine. Energy, 58, 483–493. ANSYS user's guide Hoseini, S. H. Jahromi, S. H. M. & Vahid, M. S. R. (2013). Determination of Discharge Coefficient of Rectangular Broad-Crested Side Weir in Trapezoidal Channel by CFD. International Journal of Hydraulic Engineering, 2(4), 64-70. DOI: 10.5923/j.ijhe.20130204.02 Lodomez, M., Erpicum, S., Dewals, B., Pirotton, M. & Archambeau, P. (2014). Comparison between Experimental and SPH Models over a Sharp-crested Weir. The 5th International Junior Researcher and Engineer Workshop on Hydraulic Structures. Spa, Belgium. Naghavi, B., Esmaili, K., Yazdi, J, & Vahid, F.K. 2011. An experimental and numerical study on hydraulic characteristics and theoretical equations of circular weirs. Canadian Journal of Civil Engineering, 38(12): 1327–1334. doi: 10.1139/l11-092. Namaee, M. R. (2014). Numerical Investigation of a Side Weir with an Inclined Ramp. World Applied Sciences Journal, 31 (10): 1759-1766, 2014, DOI: 10.5829/idosi.wasj.2014.31.10.429 Yuce, M. I., AL-DABBAGH, M. A. & AL-BABELY, A. H. (2015). Flow simulation over oblique cylindrical weirs. Can. J. Civ. Eng., 42, 389–407. dx.doi.org/10.1139/cjce-2014-0157
Details
| Primary Language | English |
|---|---|
| Subjects | Engineering |
| Journal Section | Articles |
| Authors | |
| Publication Date | August 19, 2018 |
| Published in Issue | Year 2018Issue: 2 |
