The calculation of transport phenomena in boundary layers, pipe or duct ̄ows can be easily accomplished by a simple, zero order, mixing length formulation. The application of this model in simple engineering ̄ows, i.e., ̄ows without recirculation or asymmetry, is still widely extended because of its simplicity and its ability to match experimental results at the same degree than more elaborated mo...

By simulating the convection in the upper layers of seven diierent stars and matching these simulations to 1D mixing-length models using the same input physics, we have been able to infer the behaviour of the T-relation and the mixing-length parameter, , as the stellar parameters change. We have then used this knowledge in stellar evolution calculations, in order to investigate the consequences...

The transition to convection in a zero Prandtl number fluid with stress-free and perfectly conducting boundaries differs significantly from finite Prandtl number convection, giving rise to a three-dimensional pattern. Two possible scenarios are described and compared with recent numerical simulations by Thual Ii]. The Prandtl number of a fluid can approach zero in one of two ways either because...

This study is a linear stability analysis of the flows induced by ultrasound acoustic waves (Eckart streaming) within an infinite horizontal fluid layer heated from below. We first investigate the dependence of the instability threshold on the normalized acoustic beam width H(b) for an isothermal fluid layer. The critical curve, given by the critical values of the acoustic streaming parameter, ...

micromixers are one of the most crucial components of lab-on-a-chip devices with the intention of mixing and dispersion of reagents like small molecules and particles. the challenge facing micromixers is typically insufficient mixing efficiency in basic designs, which results in longer microchannels. therefore, it is desirable to increase mixing efficiency, in order to decrease mixing length, w...

Context. The observations of rapidly rotating stars are increasingly detailed and precise thanks to interferometry and asteroseismology; twodimensional models taking into account the hydrodynamics of these stars are very much needed. Aims. A model for studying the dynamics of baroclinic stellar envelope is presented. Methods. This models treats the stellar fluid at the Boussinesq approximation ...

Micromixers are one of the most crucial components of Lab-On-a-Chip devices with the intention of mixing and dispersion of reagents like small molecules and particles. The challenge facing micromixers is typically insufficient mixing efficiency in basic designs, which results in longer microchannels. Therefore, it is desirable to increase mixing efficiency, in order to decrease mixing length, w...