Analysis of the Impact of Curvature Correction Factor fc on the Flow Past a Two-Dimensional Bluff Body

This paper presents an improved k-ω SST turbulence model to enhance the simulation accuracy of Bluff Body Bypassing Problems (BBBPs) within the Reynolds-Averaged Navier–Stokes (RANS) framework. Although RANS methods are computationally efficient, they are limited in resolving instantaneous turbulent fluctuations, which often results in significant errors when predicting turbulent kinetic energy variations in complex flows. To address this, a curvature correction factor (fc) is introduced into the production term (Pk) of the turbulent kinetic energy equation. This factor is derived from the local fluid rotational rate, enabling the model to better account for streamline curvature effects and unsteady vortex dynamics. The modified model, along with the baseline k-ω SST formulation, is applied to two-dimensional (2D) square column flow cases. Numerical results show that the corrected model significantly improves predictive accuracy, reducing the error in the time-averaged drag coefficient (CD) from 24% to 8.3%, thereby demonstrating its effectiveness in capturing key flow characteristics around bluff bodies.