TRANSITION OF SEPARATED SHEAR-LAYER FROM ORDER TO CHAOS

Transition of the separated shear layer has been experimentally invest igated for the Reynolds numbers (based on the diameter) ranging from 2 .4x10(3) to 2.0x10(4). The degree of chaotic behavior of the separated shear layer is verified by applying ideas from nonlinear dynamics (su ch as Lyapunov exponents, correlation dimension and entropy) to the ex perimental data, thus relating the evolution of the separated shear la yer from the laminar to the weak turbulence to the concept of chaos. T he results demonstrate that the transition of the separated shear laye r from order to chaos is through one Hopf bifurcation and the periodic bifurcation. (C) 1997 American Institute of Physics.