  Generalized wall-functions in application to high-Reynolds-number turbulence
models are derived. The wall-functions are based on transfer of a boundary
condition from a wall to some intermediate boundary near the wall (usually the
first nearest to a wall mesh point but that is not obligatory). The boundary
conditions on the intermediate boundary are of Robin-type and represented in a
differential form. The wall-functions are obtained in an analytical
easy-to-implement form, take into account source terms such as pressure
gradient and buoyancy forces, and do not include free parameters. The
log-profile assumption is not used in this approach. Both Dirichlet and Newman
boundary-value problems are considered. A method for complementing solution
near a wall is suggested. Although the generalized wall-functions are realized
for the k-epsilon model, generalization to other turbulence models looks quite
clear. The general approach suggested is applicable to studying
high-temperature regimes with variable laminar viscosity and density. A robust
numerical algorithm is proposed for implementation of Robin-type
wall-functions. Preliminary test results made for a channel flow showed good
accuracy and a weak dependence of the solution on the location of the
intermediate boundary where the boundary conditions are set.
