Numerical Techniques for the Prediction of the Aerodynamic Behavior of a Complex Projectile

Abstract

Aerodynamic coefficients are predicted by traditional, uncoupled computational fluid dynamics (CFD) and coupled CFD/rigid body dynamics simulations on a complex, canard-controlled projectile. The projectile is considered in its uncontrolled state as well as for canard deflection angles such that pure pitching motion is induced. Static and dynamic aerodynamic coefficients are considered for each of the component contributions (i.e. body-fin with interference effects and individual canards). For the non-deflected canards, the aerodynamic model is equally well described by either method. The coupled simulations are completed in roughly the same total CPU time with greater angular resolution than the traditional, uncoupled CFD. For the cases with deflected canards, the traditional, uncoupled CFD was able to isolate additional dependencies: (1) angle of attack as well as canard deflection angle dependency for the body-fin interference effect, and (2) a deflection angle as well as a local angle-ofattack dependency on the canard aerodynamic coefficients.