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The goal of this study is to determine whether an unsteady formulation of a RANS turbulence model leads to improved description of incompressible separated turbulent flows around two-dimensional bodies. Two geometries are considered: a NACA 4412 airfoil and a circular cylinder. Simulations are conducted with two-equation turbulent models: Menter's 1994 Shear Stress Transport model and Wilcox's 2006 -model, implemented in the opensource CFD OpenFOAM software. Comparison with experimental data and computational results obtained from Large and Detached Eddy Simulations as well as with URANS/RANS models by other research groups is also provided. Nomenclature Re = Reynolds number, U ∞ ρ/ v M = Mach number, U ∞ /a ρ = density P = pressure a = speed of sound U ∞ = free stream velocity u = streamwise velocity component = vertical velocity component u' = velocity fluctuation in the streamwise direction I = turbulence intensity, v = kinematic viscosity  = dynamic viscosity c = chord C p = pressure coefficient, C pb = base pressure coefficient at C D = drag coefficient, C L = lift coefficient, C f = friction coefficient, A = frontal area F D = drag force 1 Graduate Student, Mechanical Engineering, MSC01 1105, 1 UNM Albuquerque, NM, 87131-00011, AIAA Student Member. 2 F L = lift force D = diameter = wall shear stress = friction velocity, x = streamwise flow direction y = normal-to-wall direction y + = dimensionless distance from the wall based on fluid properties, y w = distance between a wall and the first grid node in the y-direction t = time t* = dimensionless time = azimuth angle measured clockwise from the stagnation point = separation angle measured clockwise from the stagnation point α = angle of attack ω = turbulent specific dissipation, ε/ k ε = turbulent scalar dissipation k = turbulent kinetic energy = blending constant, L R = recirculation length h = characteristic mesh length for the constant domain size, N = total number of nodes in the computational domain