Nonequilibrium velocity fluctuations and energy amplification in planar Couette flow

In this paper we investigate intrinsic thermally excited nonequilibrium velocity fluctuations in laminar planar Couette flow. For this purpose we have complemented the solution of the stochastic Orr-Sommerfeld equation for the intensity of the fluctuations of the wall-normal velocity, presented in a...

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Detalles Bibliográficos
Autores: Ortiz De Zárate Leira, José María, Sengers, Jan V.
Tipo de recurso: artículo
Fecha de publicación:2009
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/44402
Acceso en línea:https://hdl.handle.net/20.500.14352/44402
Access Level:acceso abierto
Palabra clave:536
Rayleigh-Benard Convection
Shear Flows
Hydrodynamic Fluctuations
Light-Scattering
Polymer-Solution
Liquid-Mixture
Q Divergence
Instability
Stability
Fluid
Termodinámica
2213 Termodinámica
Descripción
Sumario:In this paper we investigate intrinsic thermally excited nonequilibrium velocity fluctuations in laminar planar Couette flow. For this purpose we have complemented the solution of the stochastic Orr-Sommerfeld equation for the intensity of the fluctuations of the wall-normal velocity, presented in a previous publication, with a solution of the stochastic Squire equation for the intensity of the fluctuations of the wall-normal vorticity. We have obtained exact solutions of these equations without boundary conditions and solutions in a Galerkin approximation when appropriate boundary conditions are included. These results enable us to make a quantitative assessment of the intensity of these nonequilibrium fluctuations, as well as of the related energy amplification, which are always present, even in the absence of any externally imposed noise.