6533b872fe1ef96bd12d390b

RESEARCH PRODUCT

High Reynolds number Navier-Stokes solutions and boundary layer separation induced by a rectilinear vortex

Marco SammartinoFrancesco GarganoVincenzo Sciacca

subject

D'Alembert's paradoxGeneral Computer SciencePrandtl numberMathematics::Analysis of PDEsFOS: Physical sciencesPhysics::Fluid Dynamicssymbols.namesakeMathematics - Analysis of PDEsHagen–Poiseuille flow from the Navier–Stokes equationsFOS: MathematicsSettore MAT/07 - Fisica MatematicaMathematical PhysicsMathematicsMathematical analysisGeneral EngineeringFluid Dynamics (physics.flu-dyn)Reynolds numberPhysics - Fluid DynamicsMathematical Physics (math-ph)Non-dimensionalization and scaling of the Navier–Stokes equationsBoundary layersymbolsTurbulent Prandtl numberReynolds-averaged Navier–Stokes equationsBoundary layer Unsteady separation Navier Stokes solutions Prandtl’s equation High Reynolds number flows.Analysis of PDEs (math.AP)

description

Abstract We compute the solutions of Prandtl’s and Navier–Stokes equations for the two dimensional flow induced by a rectilinear vortex interacting with a boundary in the half plane. For this initial datum Prandtl’s equation develops, in a finite time, a separation singularity. We investigate the different stages of unsteady separation for Navier–Stokes solution at different Reynolds numbers Re = 103–105, and we show the presence of a large-scale interaction between the viscous boundary layer and the inviscid outer flow. We also see a subsequent stage, characterized by the presence of a small-scale interaction, which is visible only for moderate-high Re numbers Re = 104–105. We also investigate the asymptotic validity of boundary layer theory by comparing Prandtl’s solution to Navier–Stokes solutions during the various stages of unsteady separation.

https://dx.doi.org/10.48550/arxiv.1310.6623