Bluff bodies can be prone to well-known self-excited instability such as galloping. Opposite to classical and well documented Vortex Induced Vibrations (VIV), oscillation amplitude is not bounded in such a way galloping-like instability can alter the integrity of the structure on short term. Although stability criteria exist in the literature , there is a real lack considering the cause and the way to inhibit such instability.
It is consequently proposed in this paper to investigate the flow over the classical ‘non-circular’ structure, i.e. the square box body, by means of advanced Spectral Large Eddy Simulation (LES) solver, ,  & . The main objectives of this numerical analysis will be to provide an accurate solution to underline the possible mechanisms that trigger the instability as well as a base solution for future wake stability & control analysis, .