Symmetry breaking in a 3D bluff-body wake
Center for Turbulence Research Proceedings of the Summer Program
MetadataShow full item record
Rigas, G., Esclapez, L., & Magri, L. Symmetry breaking in a 3D bluff-body wake. Center for Turbulence Research Proceedings of the Summer Program. https://doi.org/10.17863/CAM.35424
The dynamics of a three-dimensional axisymmetric blu -body wake are examined at low Reynolds regimes where transitions take place through spatio-temporal symmetry breaking. A linear stability analysis is employed to identify the critical Reynolds num- ber associated with symmetry breaking, and the associated eigenmodes, known as global modes. The analysis shows that the axisymmetric stable base ow breaks the rotational symmetry through a pitchfork m = 1 bifurcation, in agreement with previously reported results for axisymmetric wakes. Above this threshold, the stable base ow is steady and three-dimensional with planar symmetry. A three-dimensional global stability analysis around the steady re ectionally symmetric base ow, assuming no homogeneous direc- tions, predicts accurately the Hopf bifurcation threshold, which leads to asymmetric vortex shedding. DNS simulations validate the stability results and characterize the ow topology during the early chaotic regime.
Royal Academy of Engineering (RAEng)
External DOI: https://doi.org/10.17863/CAM.35424
This record's URL: https://www.repository.cam.ac.uk/handle/1810/288109