DYNAST: Dynamic Stability of Capsules and Blunt Bodies at Angle of Attack

Abstract

The study aims to improve the IXV aeroshape by implementing small wings to allow passing the transonic flight regime at angle of incidence below 40°, improving static stability in subsonic and achieving L/D>1. Two numerically optimized configurations are investigated. Static and dynamic aerodynamic coefficients are determined experimentally in the range 0.5≤Ma≤2.0 applying force measurement and free oscillation technique. At representative conditions static numerical simulations are performed. Dynamic coefficients are also determined, using two approaches: Fully coupled URANS/RBD-simulation of a free oscillation and hybrid RANS/LES-simulation of a prescribed motion. All results coincided well at Ma=2.0, but differ for transonic and subsonic cases. An experimentally built AEDB is used for flight performance analysis which proves to be promising in decreasing trim angle and increasing L/D-ratio. The configurations are found to be either statically stable, indifferent or only slightly unstable. Dynamically, only damped oscillations are recorded. Though, the modified aeroshape seems to overcome the stability issues of IXV in the transonic range.