Abstract
Numerical study is performed on the flow of incompressible fluid driven in a square cavity. Behavior of the unsteady flows beyond the first Hopf bifurcation is investigated. The first Hopf bifurcation is localized at Re_<cr> = 7987 with the fundamental frequency f = 0.4512, in good agreement with the previous studies. The secondary Hopf bifurcation occurs at 9600< Re_<cr2> ≤ 9800. Quasi-periodic solution at Re = 10000 exhibits frequencies f_1 = 0.4381 and f_2 = 0.7128. Solution loses one frequency at 10800 < Re_<cr3> < 11200 and bistable periodic solutions with different fundamental frequencies appear for higher Reynolds numbers. It is shown that the latter bifurcation is of subcritical nature.
