The paper is devoted to the study of formation stratification in an incompressible fluid due convective laminar flows horizontal layers heated from side. Medium and intensive modes stationary thermal, concentrational thermo-concentrational (in particular thermohaline) convection are considered, which nonlinear flow features manifested, can radically change structure characteristics heat mass tr...

Wall-bounded flows experience a transition to turbulence characterized by the coexistence of laminar and turbulent domains in some range of Reynolds number R, the natural control parameter. This transitional regime takes place between an upper threshold Rt above which turbulence is uniform (featureless) and a lower threshold Rg below which any form of turbulence decays, possibly at the end of o...

Fertilization is a complex interaction among biological traits of gametes and physical properties of the fluid environment. At the scale of fertilization (0.01-1 mm), sperm encounter eggs while being transported within a laminar (or viscous) shear flow. Varying laminar-shear in a Taylor-Couette flow tank, our experiments simulated important aspects of small-scale turbulence within the natural h...

We consider the propagation of laminar premixed flames in the presence of a parallel flow whose scale is smaller than the laminar flame thickness. The study addresses fundamental aspects with relevance to flame propagation in narrow channels, to the emerging micro-combustion technology, and to the understanding of the effect of small scales in a (turbulent) flow on the flame structure. In part,...

This paper examines the evolution of closing Reynolds-averaged Navier–Stokes equations by approximating Reynolds stresses via second-moment transport themselves. strategy first proposed Rotta is markedly in contrast to more usual approach computing an effective “turbulent viscosity” deduce turbulent as a Newtonian fluid laminar motion. covers main elements development this and shows examples ap...

The paper describes the implementation details and validation results for an agglomeration multigrid procedure developed in the context of hybrid, unstructured grid solutions of aerodynamic flows. The procedure is applied to the solution of 2-D, laminar viscous flows of aerospace interest. The governing equations are discretized with an unstructured grid finite volume method which is capable of...

Recently, version 3.0a of the software package FEMLAB for solving multiphysics partial differential equations was released. In the present project we compared its performance with the previous release 2.3 and the package Fluent 6.1 in stationary laminar flow benchmark problems in two and three dimensions. It turns out that the new version is an essential improvement over the old version. It is ...

We investigate the type I modes of instability within the compressible boundary-layer flow over a rotating cone, defined by general half angle ψ. The work extends previous studies into the compressible rotatingdisk flow (ψ = 90o) and incompressible rotating-cone flows. Generalised compressible von Kármán equations are established and solved numerically to give the laminar-flow profiles. We then...

In this work, we consider the feedback control of flows within the vertical Bridgman crystal growth process. We investigate the use of crucible rotation, via feedback control algorithms, in suppressing oscillatory flows in two prototypical vertical Bridgman crystal growth configurations—a laminar flow regime driven by a time-oscillatory furnace disturbance and a time-varying regime driven by st...