subsurface drainage systems are used to control the depth of the water table and to reduce or prevent soil salinity. water flow in these systems is described by the boussinesq equation, and the advection-dispersion equation coupled with the boussinesq equation is used to study the solute transport. the objective of this study was to propose a finite difference solution of the advection-dispersi...

The present work involves numerical simulation of a steady, incompressible forcedconvection fluid flow through a matrix of porous media between two parallel plates at constanttemperature. A Darcy model for the momentum equation was employed. The mathematical model forenergy transport was based on single phase equation model which assumes local thermal equilibriumbetween fluid and solid phases. ...

20 The Boltzmann transport equation describes the statistical behavior of particles that are interacting with surrounding media. The transport equation is used to simulate neutral particle physics in many physical systems–for example, combustion systems, nuclear power reactors, and internal confinement fusion. Unfortunately, many iterative schemes, based on an explicit scattering and re-emissio...

dispersivity (?) and effective transport porosity (?eff) are input parameters in equilibrium convection dispersion equation (cde). normally these parameters are obtained from breakthrough curves by inverse method. however, obtaining breakthrough curves in the field is not often possible in practice. the objective of this study was to estimate ? and feff from soil hydraulic data. for this purpos...

Dynamical symmetries of the collisionless Boltzmann transport equation, or Vlasov equation, but under the influence of an external driving force, are derived from non-standard representations of the 2D conformal algebra. In the case without external forces, the symmetry of the conformally-invariant transport equation is first generalized by considering the particle momentum as an independent va...

For a system of noninteracting electrons scattered by neutral impurities, we derive a modified Boltzmann equation that includes quasiparticle and virial corrections. We start from a quasiclassical transport equation for nonequilibrium Green’s functions and apply a limit of small scattering rates. The resulting transport equation for quasiparticles has gradient corrections to scattering integral...