We consider a Vlasov-Fokker-Planck equation governing the evolution of the density of interacting and diffusive matter in the space of positions and velocities. We use a probabilistic interpretation to obtain convergence towards equilibrium in Wasserstein distance with an explicit exponential rate. We also prove a propagation of chaos property for an associated particle system, and give rates o...

In this article a model of water diffusion within bonded assembly will be set up. It fed by experimental tests which allow to characterize the diffusive properties taking into account presence interphases. For purpose, specimens instrumented with Fresnel fiber optic sensors. These sensors local measurement content polymer material during wet ageing. Once these measurements are performed, model,...

in this paper the propagation of harmonic plane waves in a homogeneous anisotropic magneto-piezothermoelastic diffusive body with fractional order derivative is studied. the governing equations for a homogeneous transversely isotropic body in the context of the theory of thermoelasticity with diffusion given by sherief et al. [1] are considered as a special case. it is found that three types of...

Observations suggest that the timeand zonal-mean state of the extratropical atmosphere adjusts itself such that the so-called ‘‘criticality parameter’’ (which relates the vertical stratification to the horizontal temperature gradient) is close to one. T. Schneider has argued that the criticality parameter is kept near one by a constraint on the zonal momentum budget in primitive equations. The ...

We are interested in modelling and control of a salt gradient solar pond (SGSP) in the south of Tunisia. We developed a model of a Closed Cycle Salt Gradient Solar Pond (CCSGSP) that ensure successful year round operation of the pond. This model was used to study the response of solar pond (SP) to various control technique. It takes into account heat and salt diffusion in the pond and simulates...

Spreading of bacteria in a highly advective, disordered environment is examined. Predictions of super-diffusive spreading for a simplified reaction-diffusion equation are tested. Concentration profiles display anomalous growth and super-diffusive spreading. A perturbation analysis yields a crossover time between diffusive and super-diffusive behavior. The time’s dependence on the convection vel...

FOR OSMOREGULATING vertebrates, diffusive water loss is an unavoidable consequence of living in seawater. Marine teleost fish drink seawater to offset this diffusive water loss dictated by the steep osmotic gradient between blood and the surrounding seawater, a water loss occurring mainly across the gills. Imbibed seawater is processed along the gastrointestinal tract by desalinizing the medium...

In the hydrodynamic regime, the evolution of a stochastic lattice gas with symmetric hopping rules is described by a diffusion equation with densitydependent diffusion coefficient encapsulating all microscopic details of the dynamics. This diffusion coefficient is, in principle, determined by a Green– Kubo formula. In practice, even when the equilibrium properties of a lattice gas are analytica...

In the hydrodynamic regime, the evolution of a stochastic lattice gas with symmetric hopping rules is described by a diffusion equation with densitydependent diffusion coefficient encapsulating all microscopic details of the dynamics. This diffusion coefficient is, in principle, determined by a Green– Kubo formula. In practice, even when the equilibrium properties of a lattice gas are analytica...

We report basic results from new numerical simulations of passive scalar mixing at Schmidt numbers (Sc) of the order of 1000 in isotropic turbulence. The required high grid-resolution is made possible by simulating turbulence at very low Reynolds numbers, which nevertheless possesses universality in dissipative scales of motion. The results obtained are qualitatively consistent with those based...