We consider the moment equations for a kinetic model describing the interaction of monochromatic photons with gas-particles endowed with two internal energy levels. In the space-homogeneous case the stability of the equilibrium solution is analytically proven and numerically tested. In the...

The modified Craig–Sneyd (MCS) scheme is a promising splitting scheme of the ADI type for multi-dimensional pure diffusion equations having mixed spatial-derivative terms. In this paper we investigate the extension of the MCS scheme to two-dimensional convection–diffusion equations with a...

A kinetic approach to a mixture of gases whose particles interact by elastic scattering and by a bimolecular chemical reaction is analyzed by means of the relevant Boltzmann-like equation. Conservation laws and moment equations are considered, and, improving previous results in the literature,...

During these years several hydrodynamic-like models for simulating carrier transport in semiconductors have been developed. In this paper we check the consistency of these models with the Onsager Reciprocity Principle, which is one of the fundamental principles of Linear Irreversible...

Relaxation-time approximations of the collisional operator of the Boltzmann transport equation are used for simulating carrier transport in silicon semiconductors. Solutions of these kinetic models are obtained through the use of exact-integral representations in the stationary and homogeneous...

Anomalous diffusive transport arises in a large diversity of disordered media. Stochastic formulations in terms of continuous time random walks (CTRW) with transition probability densities presenting spatial and/or time diverging moments were developed to account for anomalous behaviours. Many...

Small-scale models in the form of random walks, combining Gaussian jumps, advection by mean flow field and possibly very long sorbing durations, correspond to experimental data in many porous media, in the laboratory and in the field. Within this frame-work, solutes are observed in two phases,...

The object of this work is to calculate the effective dielectric constant tensor of a warm plasma made of non point-like ions in an electron gas whose screening length is much larger than the inter-ionic and inter-electronic distances. In this disordered medium, a proper treatment of the...