Comparative study of experimental and CFD analysis for predicting discharge coefficient of compound broad crested weir

Abstract

Present study highlights the behavior of weir crest head and width parameter on the discharge coefficient of compound broad crested (CBC) weir. Computational fluid dynamics model (CFD) is validated with laboratory experimental investigations. In the discharge analysis through broad crested weirs, the upstream head over the weir crest (h) is crucial, where the result is mainly dependent upon the weir crest length (L) in transverse direction to flow, water depth from channel bed. Currently, minimal investigations are known for CFD validations on compound broad crested weirs. The hydraulic research for measuring discharge numerically is carried out using FLOW 3D software. The model applies renormalized group (RNG) using volume of fluid (VOF) method for improved accuracy in free surface simulations. Structured hexagonal meshes of cubic elements define discretized meshing. The comparative analysis of the numerical simulations and experimental observations confirm the performance of CBC weir for precise measurement of a wide range of discharges. Series of CFD model studies and experimental validation have led to constant range of discharge coefficients for various head over weir crest. The correlation coefficient of discharge predictions is 0.999 with mean error of 0.28%.

Hydraulic Behavior of Weir-Gate Structure with Rectangular Side Obstacle under Free and Submerged Flow Conditions

“…Kulkarni and Hinge [45] presented a comparative study between experimental measurements and CFD simulations to predict the discharge coefficient of compound broad-crested weirs. The results showed close alignment between the experimental and CFD values of discharge coefficients.…”

“…Machine learning techniques have been effectively employed in various hydraulic structures, including submerged radial gates and oblique side weirs [45]. Granata et al [25] demonstrated the successful integration of hybrid grey wolf optimization with KELM to get precise forecasts of discharge coefficients in submerged radial gates.…”