  A rigorous asymptotic analysis of the Boltzmann equation for small Knudsen
numbers leads, in the general case, to more complicated sets of differential
equations than widely used to describe the behavior of gas in terms of
classical fluid dynamics. The present paper deals with such one that is valid
for significant temperature variations and finite Reynolds numbers at the same
time (slow nonisothermal flow equations). A finite-volume solver developed on
the open-source CFD platform OpenFOAM is proposed for computer simulation of a
slightly rarefied gas in an arbitrary geometry. Typical temperature driven
flows are considered as numerical examples. A force acting on uniformly heated
bodies is studied as well.
