Computational simulation of the atmospheric boundary layer using sub-optimal grid resolution

Abstract

This study explores simulation of turbulent atmospheric boundary layer (ABL) flow fields using reduced mesh resolution as a means for reducing time and computational requirements. A full resolution simulation is performed using previously developed flow fields, within OpenFOAM, in an effort to reproduce the statistical results of the original study. The reduced resolution simulation is run on a personal computer (PC) and the results are compared to the full resolution simulation as well as the original study. As previously observed, the sub-grid scale (SGS) model produces inaccurate results near the ground and a large z-component of the streamwise velocity gradient still exists at the top boundary. There is an exacerbation of these issues within the reduced resolution simulation, but the increase in variance and deviation of the streamwise velocity gradient from the log-law are aspects which particularly demonstrate the inadequacies of simulations with sub-optimal grid resolutions.