2D Boundary layers with pressure gradients (B)

Underlying Flow Regime 3-18 © copyright ERCOFTAC 2004

Best Practice Advice

Best Practice Advice for the UFR

The case studies associated with this UFR all demonstrate good practices, which for fully turbulent 2D boundary-layer separation in an adverse pressure gradient may be summarized as follows;

- perform grid dependency studies to eliminate sensitivities due to mesh

- assess the effect of sensitivity to boundary conditions by varying the critical inputs

- use higher order discretisation, especially on momentum

- use low-Reynolds non-linear models to capture the effect of near-wall non-isotropy and flow curvature in adverse pressure gradients. k-ω models predict separation better than the equivalent k-ε models

- LES modeling is to be recommended where ever possible

- The V2F turbulence model demonstrates good near-wall flow predictions, and should be investigated for a wider class of problems to boost confidence in its performance.

Contributors: Fred Mendonca - Computational Dynamics Ltd