The study focuses on the wake physics of the Common Research Model at low speed stall conditions using Delayed Detached Eddy Simulation. Building on earlier published results that involved a single flow condition at a high angle of attack at M_∞ = 0.25 and Re = 11.6 ? 10~6, multiple angles of attack in the stall region were simulated in order to obtain robust insight into the wake behavior in this type of flow. The influence of physical time step and the CFL number on the simulation of the wake was evaluated. The flow topology remained largely similar across the α range, with higher values generating larger recirculation areas behind the wing. The interaction between wing separation, lift, tailplane inflow and tailplane loads were described. The dynamics of the unsteady and massively separated wake was further studied using Proper Orthogonal Decomposition and Dynamic Mode Decomposition. The spectral content of the forces acting on the tailplane could be associated with energetic fluctuation structures present in the wake. At α = 16° and α = 18°, two separate fluctuation frequency regions were observed which could be associated with the recirculating flow and the transversal wake fluctuation, respectively.
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