Aerodynamic characteristics of a spinning projectile with elastic deformation

The elastic deformation of a spinning projectile with a large slenderness ratio influences its flight stability and maneuverability. Unsteady time-accurate simulation based on a dual-time stepping method and the dynamic mesh method were used to solve the unsteady Reynolds-averaged Navier-Stokes (URANS) equations and obtain the aerodynamic characteristics of a spinning projectile given continuously elastic deformation. Archival wind tunnel experimental data were used, and grid resolution and time independence studies were carried out for numerical validation at angles of attack ranging from 2.09° to 10.4°. The aerodynamic coefficients induced by spin and elastic deformation were compared to the effect of movement frequency, deformation component, Mach number and angle of attack using Fourier transform. Numerical simulations indicate that the time-averaged values and the fluctuation amplitudes of the aerodynamic coefficients increase with movement frequency; two aerodynamic components are induced by elastic deformation, one opposite and one perpendicular to the direction of deformation; nose and body deformation have different effects on the aerodynamic characteristics; and the effective angle of attack induced by elastic deformation and rolling movement decreases as the Mach number increases, thus weakening the influence of movement on the aerodynamic forces.