Abstracts:

 

We have studied the phase dynamics of flows in the Taylor-Couette system by applying a forced modulation to the upper boundary of a large aspect ratio concentric cylinders system. The experiments were carried out with three different flow patterns, Taylor, wavy and turbulent Taylor vortex flow. The results are consistent with the theoretical model proposed for each flow pattern. In a one phase variable case, the Taylor vortex flow, the perturbations diffuse along the axial direction and the response of the vortex boundary positions to the modulation is well described by a simple diffusion model. In a two phase variable case, the wavy vortex flow, the perturbations propagate as traveling waves parallel with the axis of the system when there is a strong coupling between the axial and azimuthal phase variables, and diffusively for weak coupling. The phase dynamics is governed by coupled diffusion equations. In the turbulent Taylor vortex flow, where spatial coherence coexists with the turbulent flow, the phase dynamics of the coherent structure is described by a diffusion model with a diffusion coefficient an order of magnitude larger than for the laminar Taylor vortex flow.

 

For more information see: Paper in Latex

 

Publications:

 

M. Wu and C. D. Andereck, Phase Dynamics of the Taylor-Couette Systems, Physics of Fluids, 4, 2432(1992).

M. Wu and C. D. Andereck, H. R. Brand, The Phase Dynamics of Turbulent Taylor Vortex Flow, Europhysics Letter, 19 , 587(1992).

M. Wu and C. D. Andereck, Phase Dynamics in the Taylor-Couette System , in Ordered and Turbulent Patterns in Taylor-Couette Flow, ed. by C. D. Andereck, F. Hayot, (Plenum Publishing Co., New York, 1991).

M. Wu and C. D. Andereck, Phase Dynamics of Wavy Vortex Flow, Phys. Rev. Lett. 67 , 1258(1991).

M. Wu and C. D. Andereck, Phase Modulation of Taylor Vortex Flow, Phys. Rev. A Rapid Comm. 43 , 2074(1991).