Investigation of the Influence of Chamfer Treatment on the Non-Gaussian Character of Wind Pressure Distributions on Square-section Columns

Chamfering the corners of a square cylinder is a recognized technique for flow control, yet its systematic impact on the non-Gaussian statistics of surface pressure fluctuations remains inadequately quantified. To address this, large-eddy simulations (LES) are conducted at a Reynolds number of Re = ۲.۲ × ۱۰۴ for a parametric study encompassing chamfer ratios r of ۱/۱۰, ۱/۹, ۱/۸, ۱/۷, and ۱/۶. The analysis focuses on aerodynamic force coefficients, near-wake flow structures, surface pressure coefficients (Cp), and higher-order statistics, including skewness, kurtosis, and measures of non-Gaussianity. The results demonstrate that chamfering suppresses the lateral spreading of the separated shear layers, attaches them closer to the sidewalls, and reduces the characteristic scale of the wake vortex street. Statistically, at R/L=۱/۶, the wind pressure distributions at the centers of the windward and leeward faces approximate a Gaussian profile. In stark contrast, the baseline sharp-cornered cylinder exhibits pronounced non-Gaussian behavior at the side-face center, with a maximum deviation from Gaussianity of ۷۴.۳۴%. A notable finding is the peak in intermittent pressure events at R/L=۱/۹, where the leeward-face kurtosis and skewness attain maximum values of ۸.۵۵ and -۱.۸۳, respectively. Furthermore, the most extensive non-Gaussian regions are observed at R/L=۱/۹ and ۱/۷, with the entire side face behaving non-Gaussianly at the latter ratio. This study elucidates the mechanistic link between geometric modification, wake dynamics, and the ensuing surface pressure statistics, providing a quantitative basis for optimizing bluff-body aerodynamics through corner tailoring.

کلیدواژه ها:

Corner-cut square pillar ، Large eddy simulation ، Flow field mechanism ، Square column ، Wind pressure coefficient