Journal ArticleDOI
A general classification of three-dimensional flow fields
Reads0
Chats0
TLDR
In this paper, the geometry of solution trajectories for three first-order coupled linear differential equations can be related and classified using three matrix invariants for elementary three-dimensional flow patterns defined by instantaneous streamlines for flow at and away from no slip boundaries for both compressible and incompressible flow.Abstract:
The geometry of solution trajectories for three first‐order coupled linear differential equations can be related and classified using three matrix invariants. This provides a generalized approach to the classification of elementary three‐dimensional flow patterns defined by instantaneous streamlines for flow at and away from no‐slip boundaries for both compressible and incompressible flow. Although the attention of this paper is on the velocity field and its associated deformation tensor, the results are valid for any smooth three‐dimensional vector field. For example, there may be situations where it is appropriate to work in terms of the vorticity field or pressure gradient field. In any case, it is expected that the results presented here will be of use in the interpretation of complex flow field data.read more
Citations
More filters
Journal ArticleDOI
Dual-plane PIV technique to determine the complete velocity gradient tensor in a turbulent boundary layer
TL;DR: In this paper, the authors performed simultaneous dual-plane PIV experiments in streamwise-spanwise planes in the log region of a turbulent boundary layer at a moderate Reynolds number (Reτ ∼ 1100).
Proceedings ArticleDOI
Galilean invariant extraction and iconic representation of vortex core lines
TL;DR: This work presents an approach to extracting vortex core lines independently of the frame of reference by extracting ridge and valley lines of Galilean invariant vortex region quantities, and discusses a generalization of this concept leading to higher dimensional features.
Journal ArticleDOI
Identification of Tubular Vortices in Turbulence
Hideaki Miura,Shigeo Kida +1 more
TL;DR: In this paper, a new method is proposed to extract the axes of tubular vortices in turbulence and the lococi of sectional local minimum of the pressure associated with the advection acceleration are traced numerically.
Journal ArticleDOI
On the birth of stall cells on airfoils
TL;DR: In this paper, the topology of composite flowfields reconstructed by linear superposition of the two-dimensional flow around a stalled airfoil and the leading stationary three-dimensional global eigenmode has been studied.
Journal Article
Turbulence Structure in Rough and Smooth Wall Boundary Layers
TL;DR: The rough-wall boundary layer is characterized by packets of hairpin vortices which induce low-speed regions with regular span-wise spacing as discussed by the authors, and the same types of structure are observed for the rough- and smooth-wall flows.
References
More filters
Book
Nonlinear Oscillations, Dynamical Systems, and Bifurcations of Vector Fields
TL;DR: In this article, the authors introduce differential equations and dynamical systems, including hyperbolic sets, Sympolic Dynamics, and Strange Attractors, and global bifurcations.
A Reflection on Nonlinear Oscillations, Dynamical Systems, and Bifurcations of Vector Fields
J. Guckenheimer,P. J. Holmes +1 more
TL;DR: In this paper, the authors introduce differential equations and dynamical systems, including hyperbolic sets, Sympolic Dynamics, and Strange Attractors, and global bifurcations.
Book
Differential Equations, Dynamical Systems, and Linear Algebra
Morris W. Hirsch,Steve Smale +1 more
TL;DR: In this article, the structure theory of linear operators on finite-dimensional vector spaces has been studied and a self-contained treatment of that subject is given, along with a discussion of the relations between dynamical systems and certain fields outside pure mathematics.
Journal ArticleDOI
Direct simulation of a turbulent boundary layer up to R sub theta = 1410
TL;DR: In this paper, the turbulent boundary layer on a flat plate, with zero pressure gradient, is simulated numerically at four stations between R sub theta = 225 and R sub tta = 1410.