The investigation of non-stationary separated gas flow with regard to heat exchange on the basis of the numerical simulation using non-reflecting boundary conditions

The heat exchange process at the non-stationary separated supersound, trans- and subsonic gas current developing on a surface of the cylinder set across the flow is studied. The cylinder moving together with the evenly unperturbed flow at the time moment t = 0 stop instantaneously and further becomes still. The problem consist in gas current simulation at t >0 with regard to heat exchange. The solution of the non-stationary two-dimensional Navier-Stokes equations was performed by the Arbitrary Lagrangian-Eulerian computing method. Proposed in the present paper the non-linear, non-reflecting conditions at the outer boundary of the calculation region in comparison with the application of the ordinary “mild” conditions allow one to considerably reduce the dimensions of the calculation region and to make the calculations on the sufficiently detailed calculation nets actual. The results are presented by fields of velocity vectors, pressure, density, temperature and integral characteristics as well. A good agreement with the experiment is obtained.