Time-averaged characteristics of the vortex center in turbulent recirculating flows

Numerical predictions of vortex center location under isothermal conditions of varying air and CO2 flows have been made using the Reynolds-averaged Navier-Stokes equations and modified k-epsilon turbulence model. The domain of the calculations is the near-wake region of two axisymmetric centerbody combustors of different scale. Parametric studies of the axial and radial coordinates of the primary vortex center due to the annular air flow, as well as the magnitude and location of the peak negative centerline axial velocity have been completed. The results demonstrate that the vortex characteristics depend upon the interaction of the annular and center flows.