Comparative assessment of large eddy simulation and detached eddy simulation in predicting aerodynamic and flow characteristics around a tall building
B. W. Shen, Yangjin Yuan, Huan Zhou, Zheng Zhang, Tong Zhou, Xing Zheng, Qingshan Yang
Abstract
This study evaluates the performance of three turbulence models—large eddy simulation (LES), delayed detached eddy simulation, and improved delayed detached eddy simulation (IDDES)—in predicting aerodynamic and flow characteristics around a tall building. Numerical results are validated against wind tunnel experimental data, illustrating that LES provides the most accurate predictions of mean and root mean square wind pressure and base moment coefficients. IDDES achieves a favorable balance between accuracy and computational efficiency, thereby offering a practical alternative to LES in engineering applications. Additionally, a comprehensive assessment of LES and IDDES in capturing the flow characteristics around a tall building is conducted in terms of wind velocity profiles, spectral distributions, spatial correlations, and three-dimensional vortex structures. It is demonstrated that LES is capable of accurately reproducing complex flow phenomena around a tall building, including separated shear layers and organized wake vortices. In comparison, IDDES provides predictions comparable to LES for the surrounding flow features of the tall building, while failing to adequately resolve fine-scale turbulence structures in the far wake. Moreover, the proper orthogonal decomposition analysis indicates that both LES and IDDES effectively capture the dominant energetic low-frequency structures, although subtle differences are observed in the modal energy distribution.