Abstract The unsteady flow of slender body at Mach number 0.6~1.15 and angle of attack 0°~180° is calculated by using unsteady numerical simulation DDES method. The unsteady aerodynamic characteristics, frequency characteristics and vortex flow characteristics are analyzed. The main conclusions are as follows: aerodynamic force strong unsteadiness of slender body exists in the range of angle of attack from 45° to 165°, and the amplitude of unsteady fluctuation of lateral force is particularly strong, and its instantaneous magnitude is 1/4 to 1/2 of normal force coefficient. The lateral aerodynamic force has obvious dominant frequency while the longitudinal aerodynamic force/moment has no obvious dominant frequency in the range of angle of attack from 45° to 165°. The aerodynamic frequency is mainly brought by the slender body, and the wing contributes little. Complex vortex flow on the leeward side is the main cause of unsteady aerodynamic force, which is reflected in vortex generation, vortex switching and vortex shedding.
2022, Vol. 5 
