The three types of turbulence models and stability numerical simulation studies for cylindrical flow

The characteristics of flow around pile columns beneath harbor pile-wharf docks significantly influence port hydrodynamics and sediment transport. To explore the impact of turbulent numerical simulation methods on the precision of three-dimensional pile flow, an OpenFOAM turbulence model based on the CFD method was developed. Under the condition of Reynolds number Re=3,900, this study investigates the drag coefficient, Strouhal number, mean pressure coefficient, mean velocity, and vortex structure in different near-wall value ranges y⁺=0.95~5.00 for Large Eddy Simulation (LES), the original Reynolds-averaged Navier-Stokes (RANS) turbulence model, and the RANS turbulence model with added eddy viscosity limitation formula. Results indicate that compared with previous RANS turbulence models and experimental results, the RNG κ-ε turbulence model simulates the drag coefficient and Strouhal number more accurately and captures vortices with the greatest finesse; κ-ω and κ-ω SST turbulence models simulate the Strouhal number accurately and simulate the mean pressure coefficient accurately within y⁺=0.95~2.00. All RANS turbulence models exhibit significant backward flow velocity deviations in mean velocity simulations; the LES turbulence model, at higher near-wall grid precision, provides relatively accurate hydrodynamic simulation results. Moreover, the RANS turbulence model, with added eddy viscosity limitations, captures vortex structures with greater finesse, aligning more closely with real flow behavior. Analyzing and researching the hydrodynamic characteristics of single piles under different turbulence models can provide references for hydrodynamic calculations of circular pile groups beneath harbor docks.