Recent observations indicate that fully convective stars can effectively build magnetic fields without the aid of a tachocline of shear, that those fields can possess large-scale components, and that they may sense the effects of rotation. Motivated by these puzzles, we present global threedimensional simulations of convection and dynamo action in the interiors of fully convective Mdwarfs of 0....

This study is focused on the entropy production due to laminar forced convection in the entrance region of a concentric cylindrical annulus. The present hydrodynamic and temperature fields are obtained numerically. Local entropy generation distributions are obtained based on the resulting velocity and temperature fields by solving the entropy generation equation. The effect of different flow pa...

Laminar mixed convection of a nanofluid consisting of water and Al2O3 in an inclined tube with heating at the top half surface of a copper tube has been studied numerically. The bottom half of the tube wall is assumed to be adiabatic (presenting a tube of a solar collector). Heat conduction mechanism through the tube wall is considered. Three-dimensional governing equations with using two-phase...

We numerically study the behavior of self-propelled liquid droplets whose motion is triggered by a Marangoni-like flow. This latter is generated by variations of surfactant concentration which affect the droplet surface tension promoting its motion. In the present paper a model for droplets with a third amphiphilic component is adopted. The dynamics is described by Navier-Stokes and convection-...

The local mass-transfer rate was investigated along the bottom wall of two-dimensional cavities of nominally rectangular shape, 100 mm wide, and aspect ratio (depth/width) 0.5. Experimental measurements were made by an electrochemical limiting current technique based on reduction of K3Fe(CN)6 at gold ultramicroelectrodes, each 10 mm wide and spaced 1 mm apart. Experiments were carried out in th...

The chromosphere of the quiet Sun is a highly intermittent and dynamic phenomenon. Three-dimensional radiation (magneto-)hydrodynamic simulations exhibit a meshlike pattern of hot shock fronts and cool expanding post-shock regions in the sub-canopy part of the inter-network. This domain might be called “fluctosphere”. The pattern is produced by propagating shock waves, which are excited at the ...

An analytical solution describing the transport of dissolved substances in heterogeneous porous media with an asymptotic distance-dependent dispersion relationship has been developed. The solution has a dispersion function which is linear near the origin (i.e., for short travel distances) and approaches an asymptotic value as the travel distance becomes infinite. This solution can be used to ch...

We investigate the origin of the experimentally observed multifractal scaling of vehicular traffic flows by studying a hydrodynamic model of traffic. We first extend and apply the formalism of generalized Hurst exponents H(q) to the case of random walkers that not only diffuse but rather also undergo nonlinear convection due to interactions with other walkers. We recover analytically, as expect...

We consider a system coupling the incompressible Navier–Stokes equations to the Vlasov– Fokker–Planck equation. Such a problem arises in the description of particulate flows. We design a numerical scheme to simulate the behavior of the system. This scheme is asymptotic-preserving, thus efficient in both the kinetic and hydrodynamic regimes. It has a numerical stability condition controlled by t...

Surface light scattering (SLS) by capillary waves was used to investigate the adsorption behavior of non-ionic sugar surfactants at the air/liquid interface. SLS by the subphase (water) followed predictions from hydrodynamic theory. The viscoelastic properties (surface elasticity and surface viscosity) of monolayers formed by octyl beta-glucoside, octyl alpha-glucoside, and 2-ethylhexyl alpha-g...