NON-ISOTHERMAL FLOW OF A RAREFIED GAS IN 3D-DOMAINS

Stationary flow with heat transfer in a gas is investigated within Rational Extended Thermodynamics. A rarefied gas is considered in the gap between two confocal elliptical cylinders or non-coaxial circular ones. In both symmetries, internal and external cylinders are kept at two different constant temperatures and a flow in the axial direction is generated. Both Couette and Poiseuille problems are studied in these two symmetries. The solutions of the linearized field equations are determined and compared with the solutions of Classical Thermodynamic. Then, some non-linear effects are investigated. It is shown that the non-linear terms are able to describe some additional effects that are present in the Kinetic Theory but cannot be obtained within Classical Thermodynamics. In particular, non-vanishing stress tensor components and an axial heat flux are recovered in addition to the classical solutions.