Author(s): Sabir Hussain; Ali Shariq; Zulfequar Ahmad

Linked Author(s):

Keywords: Computational fluid dynamics; Discharge; Flow efficiency; Linear rectangular side weir; Rectangular piano key side weir; Water surface profile

Abstract: Side weirs are important hydraulic structures that divert discharge from a primary channel to a diversion channel. Most of the studies carried out so far focus on linear rectangular and labyrinth side weirs. Sparse work has been performed on the piano key side weir. In this paper, a Computational Fluid Dynamics (CFD) based numerical study was conducted to simulate the flow over a linear rectangular side weir and a piano key side weir under subcritical approach flow. A three-dimensional (3D) multiphase model with a standard k-ε turbulence model was adopted for the flow simulation. De Marchi’s equation was validated the simulation results of a linear rectangular side weir. The results of the proposed CFD model of linear rectangular side weir were within ±10% error. The piano key side weir that was considered for flow simulation has a ratio of crest length and straight length equal to 3.25, equal width of outlet and inlet keys, and the percentage of head over the crest and crest height in the range of 0.167 to 0.833. A comparison was made between flow over linear rectangular side weir and rectangular piano key side weir regarding water surface profile, flow pattern, velocity contour, and velocity streamlines. The discharge over the rectangular piano key side weir is 1.3 to 1.67 times higher than the linear rectangular side weir. The rectangular piano key side weir was more efficient than linear rectangular side weirs.

DOI: https://doi.org/10.3929/ethz-b-000675921

Year: 2024