Gas-surface interaction and boundary conditions for the Boltzmann equation
Idioma
en
Article de revue
Este ítem está publicado en
Kinetic and Related Models. 2014, vol. 7, n° 2, p. 422-450
AIMS
Resumen en inglés
In this paper we revisit the derivation of boundary conditio ns for the Boltzmann Equation. The interaction between the wall atoms and the gas molecules within a thin surface layer is described by a kinetic equation ...Leer más >
In this paper we revisit the derivation of boundary conditio ns for the Boltzmann Equation. The interaction between the wall atoms and the gas molecules within a thin surface layer is described by a kinetic equation introduced in [10] and used in [1]. This equation includes a Vlasov term and a linear molecule-phonon collision term and is coupled with the Boltzmann equation describing the evolution of the gas in the bulk flow. Boundary conditions are formally derived from this model by using classi cal tools of kinetic theory such as scaling and systematic asymptotic expansion . In a first step this method is applied to the simplified case of a flat wall. Then it is extented to walls with nanoscale roughness allowing to obtain more complex scattering patterns related to the morphology of the wall. It is proved that the obtained scattering kernels satisfy the classical imposed properti es of non-negativeness, normalization and reciprocity introduced by Cercignani [13]< Leer menos
Palabras clave en inglés
Kinetic theory
nanoflows
surface diffusion
Orígen
Importado de HalCentros de investigación