Large Eddy Simulations of extreme pressures in low Froude number hydraulic jumps

Abstract This paper sought to assess the capability of the Large Eddy Simulation technique in reproducing the fluctuating pressures exerted on the slabs of hydraulic jump stilling basins. Using the volume-of-fluid (VOF) technique and the Smagorinsky model, three hydraulic conditions were simulated, with inflow Froude numbers equal to 2.3, 3.0 and 3.8. After grid verification, the simulations were validated through the comparison of extreme pressure quantiles and mean and standard deviation of velocities. Instantaneous pressure series extracted from the numerical simulations were compared against data from other experimental works, comprising the pressure fluctuations coefficient and dimensionless quantiles of extreme pressures. The Large-Eddy Simulation (LES) technique was found to be able to generate instantaneous pressure series of low Froude number jumps with adequate probability distributions. Intensity of pressure fluctuations and extreme pressure values acting on low Froude number stilling basins can be readily computed using the equations proposed herein.