Finite element modeling of non-equilibrium fluid-wall interaction beyond the continuum regime

Future passenger transportation will be done at speeds and altitudes higher than current civil aviation, in conditions where the Navier-Stokes equations become invalid as the atmospheric density and the residence time of fluid particles are greatly reduced. Among the many problems associated to these flight conditions, there is the fact that the flow does not fully accommodate the conditions at solid walls, and both flow velocity and temperature do not match the wall counterparts. A consistent finite element Galerkin approach is proposed to address the imposition of slip velocity and temperature jump conditions typical of such high-Mach and rarefied flows. The methodology is evaluated for flow conditions ranging from continuum to transitional.