Aerodynamic investigation of a 3.5:1 prolate spheroid

International audience; Experimental measurements, steady (RANS) and unsteady (URANS) numerical simulations are performed on a 3.5:1 prolate spheroid at angles of attack from 0° to 90°. The Reynolds number considered is ReL=2.57*1^6, corresponding to the wind tunnel conditions. CFD simulations are performed with OpenFOAM, using the k-omega SST and the Spalart-Allmaras turbulence models. Analyses of aerodynamic coefficients and surface pressure show a good agreement between CFD simulations and experimental results. The turbulent structures in the wake of the spheroid have a complex topology, strongly dependent on the angle of attack considered. Results of URANS simulations allow to identify turbulent structures that are steady and asymmetric at low angles of attack, symmetric and unsteady at higher values. The configuration at AoA=90° is the most complex with the presence of disorganized and unstable structures.