Navier Stokes Type Equations Research Articles

Incompressible Flow In Granulated PorousMedia With Null Initial Velocity: A Result OfExistence And Unicity Of Solution

In this work we study a Navier-Stokes type equation which models the flow of a viscous, homogeneous and incompressible fluid in an isotropic granular (non consolidated) porous media. Using point fixed type arguments we obtain conditions for existence and unicity of solution for the equation in Holder's spaces.

The structure of a shock wave in a fully ionized gas

The structure of a plane shock wave moving through a completely ionized plasma of protons and electrons is calculated. It is assumed that the two species of particles behave as two gases, each separately in a quasi-equilibrium state corresponding generally to two different temperatures. Navier-Stokes type equations with coefficients of viscosity and thermal conductivity appropriate to the two species are solved by numerical iteration.For very strong shocks it is found that both the velocity of electrons and protons and the temperature of the protons change in a distance about twice the mean path for momentum transfer between protons in the hot (shocked) gas. The electron temperature changes in about eight of these mean free paths, causing a relatively wide zone of hot electrons at low density ahead of the usual velocity shock-front. The density and temperature gradients of protons and electrons create an electric field.