Solitary Coherent Structures in Viscoelastic Shear Flow: Computation and Mechanism
نویسندگان
چکیده
منابع مشابه
Solitary coherent structures in viscoelastic shear flow: computation and mechanism.
Starting from stationary bifurcations in Couette-Dean flow, we compute nontrivial stationary solutions in inertialess viscoelastic circular Couette flow. These solutions are strongly localized vortex pairs, exist at arbitrarily large wavelengths, and show hysteresis in the Weissenberg number, similar to experimentally observed "diwhirl" patterns. Based on the computed velocity and stress fields...
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We report experimental discovery of a localized structure, which is of a new type for dissipative systems. It appears as a solitary vortex couple (”diwhirl”) in Couette flow with highly elastic polymer solutions. A unique property of the diwhirls is that they are stationary, in contrast to the usual localized wave structures in both Hamiltonian and dissipative systems which are stabilized by wa...
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In many applications one is interested in finding solutions to nonlinear evolution equations with a particular spatial and temporal structure. For instance, solitons in optical fibers and wave guides or buckling modes of long structures can be interpreted as localised travelling or standing waves of an appropriate underlying partial differential equation (PDE) posed on an unbounded domain. Spir...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2000
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.85.4056