Abstract:
The central-difference and upwind schemes for the convective terms of the gas dynamics
equations are considered, as well as their interaction, carried out using various transition
and weight functions. Testing was carried out on a model problem of the decay of homogeneous isotropic turbulence. Methods of large eddies with closing turbulence models
were considered. The question of the consistency of the initial field with respect to the
parameters of the turbulence model was investigated. The optimal values of the constants
of the closing turbulence model were determined, allowing, in the case of a central-difference approximation, to maintain a low level of dissipation of the kinetic energy of
turbulence in the high-frequency region of its spectrum. The weighting factor of the upwind scheme was determined, starting from which the influence of the mentioned constants becomes insignificant.
Keywords:numerical dissipation, central differences, upwind schemes, DES.