Separating Flow Behind a Back-Step. Part I. Quasi-Hydrodynamic Equations   and Computation of a Laminar Flow
  We demonstrate the results of the numerical modelling of a plane two-dimensional viscous incompressible flow in a channel with a back-step. As a mathematical model we take equations for a incompressible flow based on the quasi-hydrodynamic (QHD) equations. We present a phenomenological derivation of the QHD equations and show a relation of these equations to the Navier-Stokes system. We test the proposed numerical algorithm by computing of certain laminar flows 
T.G.Elizarova, I.S.Kalachinskaya, Yu.V.Sheretov