In this paper, a numerical aero-thermal validation has been carried out for two (02) 30:1 scaled models with ribbed internal surface reproducing an original trailing edge (TE) geometries with one row of enlarged pedestals under stationary and rotating conditions for high Reynolds numbers. The commercial ANSYS-Fluent software is used to perform a CFD analysis modeling the isothermal air flow inside the stationary geometry using the k-ω SST turbulence model. PIV and TLC experimental data were used to validate aero-thermally the numerical model; qualitatively and quantitatively for different working conditions (Re = 10000-40000 and Ro = 0-0.23), respectively. Numerical results reveal, under rotating conditions, a disappearance of the observed horse-shoe structures of the stationary conditions inside the TE exit region, a decrease of the flow approaching angle and an acceleration of its velocity beside an over prediction of the turbulence Kinetic Energy (k). The obtained results assist the understanding and the forecast of the flow field behavior by the evaluation of the aero-thermal performances of the studied blade cooling system throughout the design step.