  By analogy with the kinetic theory of gases, most turbulence modeling strate-
gies rely on an eddy viscosity to model the unresolved turbulent fluctuations.
How- ever, the ratio of unresolved to resolved scales - very much like a degree
of rarefaction - is not taken into account by the popular conventional schemes,
based on the Navier- Stokes equations. This paper investigates the simulation
of turbulent flow with a gas- kinetic scheme. In so doing, the modeling of
turbulence becomes part of the numerical scheme: the degree of rarefaction is
automatically taken into account; the turbulent stress tensor is not
constrained into a linear relation with the strain rate. Instead it is modeled
on the basis of the analogy between particles and eddies, without any as-
sumptions on the type of turbulence or flow class. The implementation of a
turbulent gas-kinetic scheme into a finite-volume solver is put forward, with
turbulent kinetic energy and dissipation supplied by an allied turbulence
model. A number of flow cases, challenging for conventional RANS methods, are
investigated; results show that the shock-turbulent boundary layer is captured
in a much more convincing way by the gas-kinetic scheme.
