Aerodynamic analysis of SD7037 airfoil with flex-skin flap at low angles of attack and low Reynolds numbers

Abed A.T.M.A., Hussein A.A., Mahdi S.H. Aerodynamic analysis of SD7037 airfoil with flex-skin flap at low angles of attack and low Reynolds numbers. Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2025, vol. 25, no. 6, pp. 1208–1219. doi: 10.17586/2226-1494-2025-25-6-1208-1219

This work concentrates on the effect of a flex-skin trailing edge flap on the aerodynamic characteristics of SD7037 airfoil at low Reynolds numbers, in the range of 2·10⁵ to 5·10⁵ using computational methods. The study used a range of angle of attack (AOA) associated with the take-off phase and different flap angles. The numerical model was set up in Siemens STAR-CCM+ package using the κ-ω shear stress transport turbulence model and the (γ-Reθ) transition model which ensured the approximate solution of Navier-Stokes equations. The verification of the computational solution was done by the comparison with the available experimental data of the plain flap, and it was discovered that the results matched pretty well at lower AoAs. Results indicated that certain sets of AoAs and flap angles can notably achieve the lift over the drag ratio above the baseline conditions, thus improved the performance especially during take-off stage. Besides, some combinations were found to be inefficient, and these were recommended to be discarded. Additionally, the results showed that the flex-skin flap generated higher lift coefficient but also higher drag coefficient at the same range of AoAs as compared to that of the plain flap.

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