A review of recent discoveries from high Reynolds number studies of turbulent boundary layers is given. The emergent regime of very large-scale structures in the logarithmic region and their subsequent influence on the near-wall cycle challenges many of the previously held assumptions regarding scaling of turbulent boundary layers at high Reynolds numbers. Experimental results are presented to ...

While much of the hemodynamics in a healthy human body has low Reynolds number, resulting in laminar flow, relatively high Reynolds number flow is observed at some specific locations, which can cause transition to turbulence. (The term “turbulence” refers to the motion of a fluid having local velocities and pressures that fluctuate randomly.) For example, the peak Reynolds number in the human a...

Scientific context Magnetic fields are important dynamically in a variety of situations in geophysics and astrophysics. Numerous observations are appearing, e.g. thanks to remote sensing and in particular to the CLUSTER ensemble of 4 satellites, allowing for an estimation of fields and of their derivatives in the Solar Wind close environment. In the magnetohydrodynamic (MHD) approximation valid...

Vesicles exposed to the human circulatory system experience a wide range of flows and Reynolds numbers. Previous investigations of vesicles in fluid flow have focused on the Stokes flow regime. In this work the influence of inertia on the dynamics of a vesicle in a shearing flow is investigated using a novel level-set computational method in two dimensions. A detailed analysis of the behaviour ...

The interaction between electric currents and a magnetic field is used to produce body (Lorentz) forces in electrolyte solutions. By appropriate patterning of the electrodes, one can conveniently control the direction and magnitude of the electric currents and induce spatially and temporally complicated flow patterns. This capability is useful, not only for fundamental flow studies, but also fo...

We present a combined theoretical and computational analysis of three-dimensional unsteady finite-Reynolds-number flows in collapsible tubes whose walls perform prescribed high-frequency oscillations which resemble those typically observed in experiments with a Starling resistor. Following an analysis of the flow fields, we investigate the system’s overall energy budget and establish the critic...

A Fourier–Chebyshev Petrov–Galerkin spectral method is described for high-accuracy computation of linearized dynamics for flow in an infinite circular pipe. Our code is unusual in being based on solenoidal velocity variables and in being written in MATLAB. Systematic studies are presented of the dependence of eigenvalues, transient growth factors, and other quantities on the axial and azimuthal...

We study the statistical properties of population dynamics evolving in a realistic two-dimensional compressible turbulent velocity field. We show that the interplay between turbulent dynamics and population growth and saturation leads to quasilocalization and a remarkable reduction in the carrying capacity. The statistical properties of the population density are investigated and quantified via...

For the eventual use as regards wave generation and damping, we investigate oscillating contact lines on vertical walls. Stainless steel is used rather than the glass of Ting and Perlin [J. Fluid Mech. 295 (1995) 263] for the vertically sinusoidally oscillating plate over a large range of Reynolds numbers. The non-wetting stainless steel minimizes the static meniscus ignored in our analysis. Ot...

This paper deals with the numerical study of bifurcations in the twodimensional lid-driven cavity. Two specific geometries are considered. The first geometry is the two-sided non facing (2SNF) cavity: the velocity is imposed on the upper and the left sides of the cavity. The second geometry is the four-sided (4S) cavity where all the sides have a prescribed motion. For the first time, the linea...