Numerical investigations of hockey groynes performance on hydrodynamic of open channels flow by using computational fluid dynamics (CFD).

Abstract

Protecting river banks from turbulent flow is crucial for sustainable development. This study aims to evaluate the performance of submerged hockey groynes on river flow characteristics. This study employs numerical simulations were conducted using ANSYS Fluent, a computational fluid dynamics (CFD) software, to examine flow patterns, mean streamlines, mean velocity profiles, bed shear stresses, and vortex kinetic energy around the groynes. The simulations utilized a laboratory flume with a hockey groyne model at three orientation angles (60°, 90°, and 120°) and three submergence ratios (75, 100, and 125%) at varying discharges (0.0057, 0.0087, and 0.0119 m³/sec). This research contributes to the understanding of submerged hockey groynes' effectiveness in riverbank protection, highlighting specific configurations that align with field requirements and offering a basis for future studies on sustainable river management strategies. The findings suggest that a submergence ratio between 75 and 100% optimizes flow characteristics, and an orientation angle of 90° provides the most effective configuration for reducing shear stress and enhancing flow stability. The validation results demonstrated that the simulations effectively modeled the flow dynamics around the groynes. A single hockey groyne exhibited a minimum scour depth, with maximum shear stresses significantly lower than those observed for a series of elliptic groynes. A direct correlation was found between bed shear stress and maximum scour across all submergence ratios and orientation angles. While the study provides valuable insights into groyne performance, the laboratory conditions may not fully replicate real-world scenarios, which could affect the generalizability of the results.