Sensitivity of inflow turbulence uncertainty on wind pressure on high‐rise buildings using large eddy simulations

Large eddy simulations (LES) can aid the prediction of wind loading on buildings, provided that representative inflow turbulence properties are prescribed. This study conducts LES to assess the sensitivity of the mean, root mean square (rms) fluctuation, and peak pressure coefficients (Cp) on building surfaces to the uncertainties in the incoming flow turbulence. Compared to wind tunnel measurements, the simulated mean Cp is well predicted, and the variation in inflow turbulence has a negligible effect. The rms Cp increases with increasing turbulence intensities and increasing turbulence length scales. Increasing inlet values of turbulence intensities and turbulence length scales reduces the root mean square errors (RMSE) of rms Cp from 0.049 to 0.026 and from 0.047 to 0.024, respectively, on the side surfaces with flow separation. The minimum Cp responds similarly, where the RMSE is reduced from 0.382 to 0.280 and from 0.385 to 0.286. The maximum Cp on the windward surface achieves the lowest RMSE of 0.089 at nominal inlet values. The agreement between LES and experiment improves significantly after incorporating uncertainties in the input turbulence properties by repeating simulations with smaller and larger values from the estimated turbulence inputs. Wind tunnel experiments often do not measure the complete turbulence properties of the incoming flow, thereby obscuring the validation process of simulation results. The findings recommend wind tunnel experiments to measure and report the complete turbulence properties of the incoming flow for accurate prediction of wind loading.