Wake transition in the flow around two circular cylinders in staggered arrangements
نویسندگان
چکیده
The wake transition of the flow around two circular cylinders placed in staggered arrangements with fixed streamwise separation of 5D and cross stream separation varying from 0D to 3D has been studied. The wake transition is compared to that of a single isolated cylinder. Linear stability analysis utilising Floquet theory and direct numerical simulations, using the spectral/hp element method were carried out. It is found that besides modes A and B, mode C can also appear in the wake transition, depending on the relative positioning of the cylinders. The structure of mode C is analysed and the non-linear character of the bifurcation for this mode is investigated.
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