Longitudinal vortices imbedded in turbulent boundary layers Part 2. Vortex pair with ‘common flow’ upwards

摘要: Detailed mean flow and turbulence measurements have been made in a low-speed turbulent boundary layer zero pressure gradient with an isolated, artificially generated vortex pair imbedded it. The vortices, by two half-delta wings on the floor of wind-tunnel settling chamber, rotate opposite directions such that ‘common flow’ between vortices is away from surface, draws boundary-layer fluid upwards. distance cores above surface grows downstream, roughly twice local thickness. cancellation circulation mixing slow, are identifiable down full length test section. As case single investigated Part 1 this series, large changes structural parameters occur.