Reza Azadi - Shockwave-turbulence interaction

Simulation of shock-wave turbulent boundary layer (TBL) interaction

Hybrid turbulence models benefit from the advantages in classic Reynolds-stress averaged models and computationally costly large eddy simulation (LES) models. In this study, several models have been utilized to explore and predict the dynamic behavior of a supersonic flow with a Mach number of 2. This flow scenario involves a strong interaction of shockwaves and turbulent boundary layers at the intake of a jet. I used the following models on the commercial software Ansys Fluent:

Steady SST k-ω,
Delayed detached eddy simulation (DDES) scale resolving (SR) model,
Shielded Detached Eddy Simulation (SDES) scale resolving (SR) model, and
Stress-Blended Eddy Simulation (SBES) scale resolving (SR) model

to simulate this complex flow.

SST k-ω model had a good approximation of the shockwaves' locations and pressure distribution on the walls compared to the experimental results. I conducted scale resolving simulations (SRS) to capture small-scale turbulence structures inside the flow field. Among the models I used, the SBES model gave the best results in the mean flow distribution and the structure of the turbulent eddies generated in the flow field. Compared to experiments, SBES showed a maximum of 9 % difference in the maximum pressure gradient at the jet's intake, which reduced the simulation error by 43 % compared to the SST k-ω model.

A snapshot view of the discretized flow domain. Here, a total number of 16 million mesh cells were used.

The Cross-sectional flow field of the intake pipe flow, far from the entrance. Contours are color-coded based on the Mach number and the velocity streamlines are inserted t the top of the plot.

Q-criterion-based isosurfaces of the flow field inside the pipe, color-coded based on the Mach number. Flow direction is from bottom to top.

Cut-view of the velocity field at the midspan of the pipe. A zoomed view is inserted to illustrate the details of the locations of the captured oblique shockwaves.