Application des techniques de contrôle des écoulements au pilotage des projectiles : Contrôle fluidique d'un projectile gyrostabilisé de 155 mm par effet Coanda

摘要

In order to increase weapons performances, manufacturers consider to produce projectiles incorporating a trajectory correction capability. The main goal is also to reduce the projectile scattering error. For aero-stabilized munitions, the control of the projectile path is carried out via airfoil surfaces, technologies mastered for decades. However, the control of a spin- stabilized projectiles is much more complex. Indeed, the flight conditions of a 155 mm spin-stabilized projectile range from high subsonic to supersonic velocities so the control device has to be adapted to all flight regimes. Moreover, the projectile has to spin to insure its stability during the flight. Then, the control devices have to be actuated at the projectile spin rate to create a significant deviation. These devices need to be low-cost and easily installed in the projectile too. This work also focuses on a promising fluidic control adapted to the previous constraints : the Coanda effect. RANS and URANS computations are performed to evaluate the aerodynamic forces generated by the Coanda effect for respectively a spinning and a non-spinning projectile. Then, 6-dof flight mechanics simulations are realized to assess the downrange and crossrange deviation of the controlled projectile. Finally, a large-eddy simulation of a simplified geometry has been conducted in order to improve our understanding of the physical mechanisms induced by the control device.