3. Framework for theoretical developments

The Chapman-Enskog theoretical approach attacks the problem by solving the Boltzmann integro-differential equation for the molecular distribution function . The solution of the equation allows us to express the transport coefficients of monoatomic gases in terms of two double integrals Ω ^(2,2) for viscosity and Ω ^(1,1) for diffusion, integrals that reflect the dynamics of the binary collision of molecules.

Collision integrals have different values depending on the choice of interaction model (Lennard-Jones 12-6 potential for non-polar gases,...