Investigation of Aerodynamic Characteristics of Swept C-Wing Configurations at Transonic Speed Using Design of Experiments and Computational Fluid Dynamics

Abstract

Authors investigated the aerodynamic characteristics of backward swept (BSCW) and forward swept (FSCW) C-wing configurations at transonic speed using Design of Experiments (DoE) and Computational Fluid Dynamics (CFD), aiming to enhance aircraft performance. Five geometric parameters for C-winglet design were identified from the literature. A quarter fractional factorial approach for the DoE was employed to analyse the effect of these parameters on aerodynamic characteristics at a constant Mach number and angle of attack of 0.8395 and 3.06°, respectively. Numerical results confirm the accuracy of the regression model in predicting aerodynamic coefficients, while normal plot highlight influential geometric parameters. Retrofitting C-winglets at the wingtips increases the aerodynamic performance by approximately 9.38% and 9.74% for BSCW and FSCW configurations respectively, compared to wings without C-winglets. The study demonstrates that utilizing a large cant angle and sweep angle of 60°, along with a low taper ratio of 0.562 for both the vertical and horizontal winglets, as well as a low cant angle of 90° for the horizontal winglet, reduces shockwave interactions on the C-winglet surface, consequently leading to a reduction in drag. It was concluded that the geometric parameters of the C-winglet play an integral role in designing new aircraft aimed at reducing drag.