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Related papers: Linear stability of flow in a 90-degree bend

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Linear modal instabilities of flow over finite-span untapered wings have been investigated numerically at Reynolds number 400, at a range of angles of attack and sweep on two wings having aspect ratios 4 and 8. Base flows have been…

We consider linear feedback flow control of the largest scales in an incompressible turbulent channel flow at a friction Reynolds number of Re$_{\tau}$ = 2000. A linear model is formed by linearizing the Navier-Stokes equations about the…

Fluid Dynamics · Physics 2020-10-20 Stephan F. Oehler , Simon J. Illingworth

In this study we revisit the problem of computing steady Navier-Stokes flows in two-dimensional unbounded domains. Precise quantitative characterization of such flows in the high-Reynolds number limit remains an open problem of theoretical…

Fluid Dynamics · Physics 2015-01-26 Jonathan Gustafsson , Bartosz Protas

Characterizing the dynamics of a cantilever in channel flow is relevant to applications ranging from snoring to energy harvesting. Aeroelastic flutter induces large oscillating amplitudes and sharp changes with frequency that impact the…

Fluid Dynamics · Physics 2019-03-11 Luis Phillipe Tosi , Tim Colonius

Direct numerical simulation is performed to study compressible, viscous flow around a circular cylinder. The present study considers two-dimensional, shock-free continuum flow by varying the Reynolds number between 20 and 100 and the…

Fluid Dynamics · Physics 2017-05-26 Daniel Canuto , Kunihiko Taira

Linear stability of solid body rotating flows with axisymmetric density variations is addressed analytically. Considering inviscid disturbances, a non trivial dispersion relation is obtained and it is shown that the instability is of…

Fluid Dynamics · Physics 2023-08-24 C. Jacques , B. Di Pierro , F. Alizard , M. Buffat , A. Cadiou , L. Le Penven

The work addresses 2D and 3D turbulent transonic flows past a wall with an expansion corner. A curved shock wave is formed upstream of a cylinder located above the corner. Numerical solutions of the Reynolds-averaged Navier-Stokes equations…

Fluid Dynamics · Physics 2015-03-31 Alexander Kuzmin

A computational study of three-dimensional instability of steady flows in a helical pipe of arbitrary curvature and torsion is carried out for the first time. The problem is formulated in Germano coordinates in two equivalent but different…

Fluid Dynamics · Physics 2019-08-29 Alexander Gelfgat

In this paper, we construct growing modes of the linearized Navier-Stokes equations about generic stationary shear flows of the boundary layer type in a regime of sufficiently large Reynolds number: $R \to \infty$. Notably, the shear…

Analysis of PDEs · Mathematics 2017-02-22 Emmanuel Grenier , Yan Guo , Toan T. Nguyen

We consider the slow flow of a viscous incompressible liquid in a channel of constant but arbitrary cross section shape, driven by non-uniform suction or injection through the porous channel walls. A similarity transformation reduces the…

Fluid Dynamics · Physics 2012-08-28 Kaare H. Jensen

We investigate by direct numerical simulation Rayleigh-B\'enard convection in a rotating rectangular cell with rotation vector and gravity perpendicular to each other. The flow is two dimensional near the onset of convection with convection…

Fluid Dynamics · Physics 2022-05-12 K. Lüdemann , A. Tilgner

In this article we consider the linear stability of the two-dimensional flow induced by the linear stretching of a surface in the streamwise direction. The basic flow is a rare example of an exact analytical solution of the Navier-Stokes…

Fluid Dynamics · Physics 2021-08-10 P. T. Griffiths , S. O. Stephen , M. Khan

This study investigates the impact of elasticity and plasticity on two-dimensional flow past a circular cylinder at Reynolds number $Re = 100$. Ten direct numerical simulations were performed using the Saramito-Herschel-Bulkley model to…

A modal stability analysis shows that pressure-driven pipe flow of an Oldroyd-B fluid is linearly unstable to axisymmetric perturbations, in stark contrast to its Newtonian counterpart which is linearly stable at all Reynolds numbers. The…

Fluid Dynamics · Physics 2020-12-09 Indresh Chaudhary , Piyush Garg , Ganesh Subramanian , Viswanathan Shankar

The identification of stream in the straight pipe as a flexible rod has allowed to present the criterion expression for determination of transition of the laminar flow regime to the turbulent as a loss of stability of the rectilinear static…

Fluid Dynamics · Physics 2007-05-23 S. L. Arsenjev , I. B. Lozovitski , Y. P. Sirik

Considering channel flow at Reynolds numbers below the linear stability threshold of the laminar profile as a generic example system showing a subcritical transition to turbulence connected with the existence of simple invariant solutions,…

Fluid Dynamics · Physics 2020-08-12 Moritz Linkmann , Florian Knierim , Stefan Zammert , Bruno Eckhardt

A variational technique is used to derive analytical expressions for the sensitivity of recirculation length to steady forcing in separated flows. Linear sensitivity analysis is applied to the two-dimensional steady flow past a circular…

Fluid Dynamics · Physics 2014-10-03 E. Boujo , F. Gallaire

We present a systematic numerical investigation of bifurcations in the two-dimensional incompressible Navier-Stokes flow past a confined circular cylinder. The results indicate that there is a qualitative correspondence between changes in…

Fluid Dynamics · Physics 2025-12-18 Jakub Cach , Karel Tůma , Jan Blechta , Sebastian Schwarzacher

Experiments have shown that flow in compliant microchannels can become unstable at a much lower Reynolds number than the corresponding flow in a rigid conduit. Therefore, it has been suggested that the wall's elastic compliance can be…

Fluid Dynamics · Physics 2022-10-25 Xiaojia Wang , Ivan C. Christov

Linear stability of stratified gas-liquid and liquid-liquid plane-parallel flows in inclined channels is studied with respect to all wavenumber perturbations. The main objective is to predict parameter regions in which stable stratified…

Fluid Dynamics · Physics 2018-02-15 Ilya Barmak , Alexander Gelfgat , Amos Ullmann , Neima Brauner