Computational investigation for free-flight aerodynamics and flight dynamics of subsonic and supersonic projectiles

In the preliminary design of modern projectiles, numerical simulations could provide the researchers with a greater detail for the flow field, aerodynamic forces and flight trajectories which are very difficult to measure accurately in wind tunnel test or real flight test. Therefore, in this paper, our research team has successfully integrated aerodynamics and flight dynamics into a computational simulation system named GMFlow to solve these coupled problems. And for GMFlow, an advanced time-accurate Navier-Stokes computational technique has been employed to compute the unsteady aerodynamics associated with the free flight of the spinning projectiles at subsonic and supersonic speeds, and an innovatively coupled computational fluid dynamics/rigid body dynamics technique has been used to determine flight trajectories of the projectiles. Unsteady numerical results obtained from the coupled method clearly display the flow field, the aerodynamic forces and moments, and the flight trajectories of the projectiles. Computed positions and orientations of the projectiles have been compared with actual data measured from free flight tests and are found to be generally in decent agreement. Therefore, the actual testing and development costs for projectiles design in the near future could be greatly reduced by the coupled technique which can accurately provide the aerodynamics and flight dynamics for these newly designed configurations.