A predictive large-eddy simulation framework for the analysis of wind loads on a realistic low-rise building geometry

Abstract

The accuracy of large-eddy simulations (LESs) for predicting wind-induced pressure loads remains an important topic of inquiry. This paper aims to advance this topic by validating an LES workflow for predicting wind pressures on a realistic low-rise building model exposed to a suburban neutral surface layer. We compare two wind tunnel data sets and LES predictions, obtained using a two-step workflow. First, we ensure that an accurate representation of the surface layer wind flow is obtained at the building location. Next, we assess the resulting wind loads on the building model. Using this workflow, we demonstrate consistent agreement between LES predictions and wind tunnel tests, where the discrepancies between the LES and wind tunnel results mimic the discrepancies between the two wind tunnel tests. This finding underscores that the pressure signals in certain locations are sensitive to inevitable, small differences in the approach flow. LES-based flow visualization uncovered that the most negative pressure peaks, which occur on the building roof, arise from hairpin-like vortices that are lifted from the separation region near the upstream roof edge. The results shed light on the complex dynamics of wind-induced pressure loads and contribute to quantifying the reliability of LES for wind load estimation.