The linear response to stochastic and optimal harmonic forcing of small coherent
perturbations to the turbulent channel mean flow is computed for Reynolds numbers ranging …

Reducing skin friction is important in nature and in many technological applications. This
reduction may be achieved by reducing stresses in turbulent boundary layers, for instance …

Free-stream turbulence (FST) is perhaps the most important source inducing by-pass
transition in boundary layer flows. The present study describes the initial energy growth of …

The optimal energy growth of perturbations sustained by a zero pressure gradient turbulent
boundary is computed using the eddy viscosity associated with the turbulent mean flow. It is …

It has recently been found by using temporal and spatial numerical simulations that steady
optimal streaks of moderate amplitude, ie, sufficiently large but not exceeding the critical …

The linear global instability and resulting transition to turbulence induced by an isolated
cylindrical roughness element of height) roughness element sustaining only the sinuous …

Separation on the rear-end of an Ahmed body is suppressed by means of large-scale
coherent streaks forced on the roof of the model. These streaks originate from an array of …

Global stability analysis and direct numerical simulation of boundary layers with an isolated
roughness element Page 1 J. Fluid Mech. (2022), vol. 949, A12, doi:10.1017/jfm.2022.749 Global …

Control of oblique breakdown in a supersonic boundary layer at Mach 2.0 using a local
cooling strip is investigated by direct numerical simulation. Previous studies have indicated …

Classical vortex generators, known for their efficiency in delaying or even inhibiting
boundary layer separation, are here shown to be coveted devices for transition to turbulence …