Search results for "Blasius boundary layer"

showing 6 items of 6 documents

Existence and Singularities for the Prandtl Boundary Layer Equations

2000

Prandtl's boundary layer equations, first formulated in 1904, resolve the differences between the viscous and inviscid description of fluid flows. This paper presents a review of mathematical results, both analytic and computational, on the unsteady boundary layer equations. This includes a review of the derivation and basic properties of the equations, singularity formation, well-posedness results, and infinite Reynolds number limits.

Applied MathematicsMathematical analysisPrandtl numberComputational MechanicsReynolds numberBoundary layer thicknessPhysics::Fluid Dynamicssymbols.namesakeBoundary layerInviscid flowBlasius boundary layersymbolsTurbulent Prandtl numberReynolds-averaged Navier–Stokes equationsMathematicsZAMM
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On the Prandtl Boundary Layer Equations in Presence of Corner Singularities

2014

In this paper we prove the well-posedness of the Prandtl boundary layer equations on a periodic strip when the initial and the boundary data are not assigned to be compatible.

Partial differential equationApplied MathematicsPrandtl numberMathematics::Analysis of PDEsGeometryMixed boundary conditionBoundary layer thicknessRobin boundary conditionBoundary layersymbols.namesakeBoundary layerBlasius boundary layerAnalytic normsymbolsBoundary value problemIncompatible dataSettore MAT/07 - Fisica MatematicaMathematicsActa Applicandae Mathematicae
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Group analysis and similarity solutions of the compressible boundary layer equations

1989

In this paper the application of Lie's methods to the equations of the laminar boundary layer is discussed. The momentum and energy equations in Prandtl's form are considered for a steady, viscous, compressible laminar flow with non zero pressure gradient, variable viscosity and thermal conductivity. Group analysis yields similarity solutions for given pressure distributions and particular values of the invariance group parameters (group classification). Crocco's transformation is obtained for the infinite-dimensional group of the Lie's algebra admitted by the equations.

Group (mathematics)Mechanical EngineeringMathematical analysisPrandtl numberLie groupLaminar flowCondensed Matter PhysicsBoundary layer thicknessSimilarity solutionPhysics::Fluid Dynamicssymbols.namesakeBoundary layerMechanics of MaterialsBlasius boundary layersymbolsMathematicsMeccanica
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Boundary value problem with integral condition for a Blasius type equation

2016

The steady motion in the boundary layer along a thin flat plate, which is immersed at zero incidence in a uniform stream with constant velocity, can be described in terms of the solution of the differential equation x'''= -xx'', which satisfies the boundary conditions x(0) = x'(0) = 0, x'(∞) = 1. The author investigates the generalized boundary value problem consisting of the nonlinear third-order differential equation x''' = -trx|x|q-1x'' subject to the integral boundary conditions x(0) = x'(0) = 0, x'(∞) = λ∫0ξx(s) ds, where 0 0 is a parameter. Results on the existence and uniqueness of solutions to boundary value problem are established. An illustrative example is provided.

integral boundary conditionsApplied Mathematics010102 general mathematicsMathematical analysisBoundary (topology)lcsh:QA299.6-433Mixed boundary conditionBlasius equationlcsh:Analysisboundary layer01 natural sciencesRobin boundary condition010101 applied mathematicssymbols.namesakeexistence and uniqueness of solutionsDirichlet boundary conditionBlasius boundary layersymbolsFree boundary problemNeumann boundary conditionBoundary value problem0101 mathematicsAnalysisMathematicsNonlinear Analysis
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Boundary-layer Flows Past an Hemispherical Roughness Element: DNS, Global Stability and Sensitivity Analysis

2015

Abstract We investigate the full three-dimensional instability mechanism arising in the wake of an hemispherical roughness element immersed in a laminar Blasius boundary layer. The inherent three-dimensional flow pattern beyond the critical Reynolds number is characterized by coherent vortical structures called hairpin vortices. Direct numerical simulation is used to analyze the formation and the shedding of hairpin packets inside the shear layer. The first bifurcation characteristics are investigated by global stability tools. We show the spatial structure of the linear direct and adjoint global eigenmodes of the linearized Navier-Stokes operator and use structural sensitivity analysis to …

TriGlobal Linear StabilityDirect numerical simulation02 engineering and technologyWake01 natural sciencesInstability010305 fluids & plasmasPhysics::Fluid Dynamicssymbols.namesake0203 mechanical engineeringHairpin vortices0103 physical sciencesPhysics020301 aerospace & aeronauticsRoughness ElementHairpin vortices; Roughness Element; TriGlobal Linear Stability; Mechanical EngineeringMechanical EngineeringReynolds numberLaminar flowGeneral MedicineMechanicsVortexBoundary layerClassical mechanicsBlasius boundary layersymbolsProcedia IUTAM
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Two-Dimensional Boundary Layer Equations: High Resolution Capturing Methods

1993

In this paper we apply the piecewise hyperbolic and parabolic essentially non-oscillatory (ENO) capturing schemes (see [2] and [4]) to approximate the solution to the boundary layer equations for two-dimensional incompressible flow. We have tested several numerical examples analyzing their resolutive power and efficiency with respect to small values of the kinematic viscosity of the flow.

Physics::Fluid DynamicsBoundary layerFlow (mathematics)Incompressible flowMathematical analysisBlasius boundary layerPiecewiseHigh resolutionPower (physics)Mathematics
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