Large-eddy Simulation of boundary layer bypass transition

Large-eddy Simulation of boundary layer bypass transition

Internship Description

Large-eddy simulation is a viable approach to investigate high Reynolds number wall-bounded turbulent flows. In this project we will simulate bypass transition of the boundary layer on a flat plate. 

Transition of incompressible boundary layer flow requires perturbations with specific features. Perturbation could come from wall, or out of the boundary layer. Study of incompressible transition mainly employ either DNS or LES. For perturbations from the wall, refer to Sayadi &Moin (JFM, 2013). Based on the perturbation function difference, H transition and K transition can be defined. It is interesting to do LES of transition with wall perturbations. From the LES model purpose, this is a useful test to evaluate the performance of SGS model in the transition behavior. From physical viewpoint, this LES study with a large computational domain can provide more information for the turbulent boundary layer development.
We have some progress before for this LES study. However, at that stage, wall normal is uniform mesh thus total 464 mesh is not sufficient to extend to large domain. Since now stretching mesh can be used in wall-normal direction, Cases could be re-run and large domain computations are possible. 

Plan: 
Step 1, reproducing Sayadi & Moin case using LES 
Step 2, extending to large domain 
Step 3, using AB code streategy, implement turbulent separation/reattachment. ​ 

Faculty Name

Ravi Samtaney

Field of Study

​​Computational fluid dynamics