Resources

Author(s): Hugo Felippe da Silva Lui and William Roberto Wolf Shock–boundary layer interactions over the convex wall of a supersonic turbine vane are explored through a detailed analysis of extreme separation bubble events. By conditionally sampling expanding and contracting bubble states and using finite-time Lyapunov exponents together with a deforming control-volume framework, this study reveals how near-wall streaks and streamwise vortices...

Author(s): Rishish Mishra, Harish Pothukuchi, Harinadha Gidituri, and Juho Lintuvuori The interface crossing behavior of a microswimmer is strongly dependent upon the capillary number (Ca), which is defined as the ratio of swimming to interfacial forces. When the interfacial forces dominate, the swimmer gets trapped. We propose a model, where the swimmers are trapped due to a wetting-induced thermodynamic potential. The translational motion of...

Author(s): T. Preskett, M. Virgilio, P. Jaiswal, and B. Ganapathisubramani Smooth and rough wall turbulent boundary layers often occur with external pressure gradients, which affect their development. This work presents an experimental investigation of high Reynolds number boundary layers, focusing on the effect of pressure gradient history on turbulence characteristics. Taking the turbulent spectra, we isolate both the effect of pressure gradient...

Author(s): Pranav Nath and Jean-Pierre Hickey The complexity of wall-bounded turbulent flows has given rise to a variety of models that capture the essence of this physical problem. Townsend’s Attached Eddy Model (AEM) utilizes eddies that exhibit geometric scaling with their distance from the wall. In contrast, the One-Dimensional Turbulence (ODT) model is built on a completely different set of modeling assumptions. We re-write the ODT formulation...

Author(s): Yinghui Li, Filippo Coletti, Monika Colombo, Yingchao Meng, and Andrew deMello In dense suspensions, both rigid particles and deformable red blood cells (RBCs) exhibit a tendency to migrate away from the walls and towards the center of the vessel in which they flow. Here we experimentally investigate the transport of microparticles along with RBCs in bifurcating vessels, which is particularly relevant for targeted drug delivery. Via...

Author(s): Mykola Stretovych, Eddy Timmermans, and Dmitry Mozyrsky Understanding the dynamics of gas discharges is critical for numerous technological applications. While the physics of electric breakdown in gas, such as air, has been studied for many decades, the early stages of the discharge dynamics remain to be an active subject of research. In this paper we provide a simple approach that helps us understand such early stages of dynamics and...

Author(s): J. O. Oyero and A. De Wit If a denser solution of a solute A lies above a less dense solution of a solute B in the gravity field, a Rayleigh-Taylor instability can trigger convective motions which favor mixing of the two fluids. We show by numerical simulations that double-diffusive effects occuring when A and B diffuse at different rates can modify the scalings of the onset time and acceleration of the instability. Moreover, the difference...