High Reynolds Number Analysis of Flat Plate and Separated Afterbody Flow Using Non-linear Turbulence Models

The ability of the three-dimensional Navier-Stokes method, PAB3D, to simulate the e ect of Reynolds number variation using non-linear explicit algebraic Reynolds stress turbulence modeling was assessed. Subsonic at plate boundary-layer ow parameters such as normalized velocity distributions, local and average skin friction, and shape factor were compared with DNS calculations and classical theory at various local Reynolds numbers up to 180 million. Additionally, surface pressure coe cient distributions and integrated drag predictions on an axisymmetric nozzle afterbody were compared with experimental data from 10 to 130 million Reynolds number. The high Reynolds data was obtained from the NASA Langley 0.3m Transonic Cryogenic Tunnel. There was generally good agreement of surface static pressure coe cients between the CFD and measurement. The change in pressure coe cient distributions with varying Reynolds number was similar to the experimental data trends, though slightly over-predicting the e ect. The computational sensitivity of viscous modeling and turbulence modeling are shown. Integrated afterbody pressure drag was typically slightly lower than the experimental data. The change in afterbody pressure drag with Reynolds number was small both experimentally and computationally, even though the shape of the distribution was somewhat modi ed with Reynolds number.