Aeroelastic Response of Spinning Projectiles with Large Slenderness Ratio at Supersonic Speed

Abstract

Obvious aeroelastic deformation occurs in spinning projectiles with large slenderness ratio, which seriously affects flight stability and maneuverability. This paper investigates the aeroelastic response of spinning projectiles with large slenderness ratio under supersonic speed. Based on a dynamic mesh method, an unsteady numerical simulation method is developed to study the aeroelasticity of spinning projectiles by coupling aerodynamics and structural dynamics. The numerical simulation method is well validated by the experimental results of AGARD 445.6 wing flutter. Then, the aeroelastic response of spinning projectiles with large slenderness ratio is numerically explored under different flight conditions. The aeroelastic response is obtained, revealing the presence of beat vibrations and variations in response frequency. Furthermore, the influence mechanism of flight conditions on the aeroelastic response is analyzed. The results suggest that the coupling of the first two modes of the projectile caused by the spinning motion leads to the occurrence of beat vibrations in the aeroelastic response; the coupling degree of the first two modes decreases as the angle of attack increases and it increases with the increase in spinning speed; and the time−averaged deformation caused by the time−averaged aerodynamic force is beneficial to the convergence of the aeroelastic response of spinning projectiles, while the rotation−induced Magnus effect is counterproductive.

Elliptical Orbit Design Based on Air-Breathing Electric Propulsion Technology in Very-Low Earth Orbit Space

“…Since the aerodynamic force makes the spacecraft very unstable at the large slenderness ratio [36], the side-to-cross-section ratio S b /S c generally does not exceed 5. The aspirated cross-section ratio S t /S c can reach nearly 1 under proper design.…”

Experimental and Numerical Flutter Analysis Using Local Piston Theory with Viscous Correction

“…Thirdly, some researchers have carried out model verification at zero AOA while still conducting flutter analysis at higher AOAs [28][29][30][31]. Wang et al [29,31] conducted flutter analyses at different AOAs by adopting both the modified third-order piston theory and the local piston theory. The flutter speeds decreased with the increase in AOA.…”

“…However, the numerical conclusion that the flutter speed decreases more quickly when increasing the AOA at a higher baseline needs to be verified, since there are no direct test data. Furthermore, Liu et al [31] proposed a numerical method that was verified using the subsonic and transonic test data of a wing at zero AOA and conducted an analysis on supersonic spinning projectiles at large AOAs.…”