Testing the kinetic-hydrodynamic model by calculating a flow above an absorbing surface

Ju. A. Nikitchenko ; A. V. Tikhonovets

Matematičeskoe modelirovanie, Tome 32 (2020) no. 9, pp. 103-118

Résumé

The problem of flow around a thin plate of infinite magnitude installed across the flow is considered. The frontal surface of the plate absorbs gas. For calculations, we used a mathematical flow model containing a combination of the Navier–Stokes–Fourier model and the model kinetic equation of polyatomic gases. The calculations were performed for a supersonic flow with a Mach number of 2.31 for a Knudsen number of 0.1 ... 0.001 and a plate surface absorption coefficient from 0 to 1. The obtained flow fields were compared with solutions of the model kinetic equation of polyatomic gases. The drag coefficient of the plate was compared with known literature data. For all considered flow parameters, a satisfactory agreement is obtained with the known data. It is shown that there are no gaps in the derivatives of gas-dynamic parameters in the cross-linking region of the kinetic and hydrodynamic components of the model. The increase in the computational efficiency of the model with respect to the solutions of model kinetic equations is estimated. The conclusion is drawn on the suitability of the considered kinetic-hydrodynamic model for describing highly nonequilibrium flows.

Détail

Keywords: polyatomic gases, Navier–Stokes–Fourier model, model kinetic equation, combined model, dynamic nonequilibrium, absorbing surface.