Abstract

Abstract

Abstract

Bending and torsional stiffness is a key factor in controlling the bending and torsional deformation of wings with high aspect ratios, however, in the process of structural stiffness design, the bending and torsional stiffness affects the structural deformation in different degrees. Based on the CFD/CSD coupling method, this paper carries out the research on the influence of bending and torsional stiffness on static aeroelastic properties under various flight conditions using FLUENT software, and summarizes the influence of bending and torsional stiffness on the static aeroelastic properties of wings with high aspect ratios by comparing the calculation results. The results of the study show that when the angle of attack increases, the lift increment gradually decreases until the angle of attack increases to 14 degrees, and the method of obtaining further more lift by increasing the bending and torsional stiffness is no longer applicable. The lift difference between them decreases from 23.98% to 7.31% as the angle of attack increases from 2 degrees to 14 degrees. At higher Mach number and lower angle of attack conditions, increasing the wing stiffness can significantly increase the wing lift. Within a certain range of angle of attack, the larger the angle of attack, the closer the lift obtained by the elastic wing is to that obtained by the rigid wing. When the angle of attack is less than 6 degrees, increasing the bending and torsional stiffness of the wing can improve the lift and drag characteristics of the wing, but when the angle of attack is more than 6 degrees, increasing the bending and torsional stiffness of the wing reduces the lift and drag characteristics of the wing. When the wing bending and torsional stiffnesses were increased by 8.28% and 5.22% on average, respectively, the lift-resistance characteristics of the wing could be improved to 5.27% at a small angle of attack under 0.75 Ma conditions. The maximum deflection difference between the two stiffnesses of the wing is maximized at higher flight speed and smaller angle of attack, while the difference between the maximum torsion angles of the two stiffnesses of the wing is maximized at lower flight speed and larger angle of attack.