Development of vortex structures in the wake of a sharp-edged bluff body

This is the authors' abstract. We don't add key points for this paper.

The development of streamwise vortical structures in the wake of an infinitely long inclined flat plate is investigated using detached eddy simulation. The numerical model is validated by comparing with available experimental results. The spanwise vortices shed from the leading and trailing edges are captured near the body in the midspan plane and are shown to quickly dissipate in the downstream wake. The generation of streamwise vortical structures and their interaction with the large-scale spanwise vortices are elucidated using the λ2-criterion to identify the vortices. The spanwise wavelength of the streamwise vortical structures is found to lie in the range corresponding to the mode B instability reported in the previous studies of wake transition. The temporal evolution of the streamwise vortices is studied in the near-wake region. The spanwise evolution of the flow clearly indicates the role of the streamwise vortices in dissipating the spanwise structures. The streamwise vortical structures also exert an influence on the shear layer at the trailing edge resulting in a corrugated pattern during their development. Cross-sectional planes normal to the plate are also used to examine the interaction between the streamwise and spanwise vortices. This combination of two-dimensional velocity fields and contours (in planes normal and parallel to the freestream and to the plate) and three-dimensional iso-surfaces provides a more complete picture of the formation of the complex fluid structures in the flow around a bluff body.