Supersonic Aerodynamic Enhancement of Swept-Forward and Swept-Back Grid Fins Using HiFUN

In this study, the aerodynamic performance of swept-forward and swept-back grid fins is analyzed and compared with the baseline unswept grid fin configuration at supersonic Mach numbers. Computations are carried out using High-Fidelity Unstructured Computational Fluid Dynamics (HiFUN CFD) software, and the flowfield around the baseline, swept-forward, and swept-back grid fins is analyzed. The aerodynamic characteristics of the baseline grid fin were validated by comparing the computed data with experimental data, and the comparison is good. The study highlights the effects of sweep direction on aerodynamic performance, focusing on axial force, normal force, and pitching moment coefficients at supersonic Mach numbers 1.8, 2.5, and 3.5 across various angles of attack. The results demonstrate a reduction in drag coefficients for both swept configurations compared to the baseline, with the swept-back fin showing slightly better drag reduction than the swept-forward fin. Additionally, the swept-forward fin configuration exhibited marginal improvements in normal force and pitching moments, particularly at higher angles of attack. These findings emphasize the potential benefits of both swept-forward and swept-back grid fin designs, providing valuable insights into improving aerodynamic performance, lift generation, and stability in supersonic flight conditions.