R. Haoui
International Journal of Aeronautical and Space Sicences, vol. 12, no. 2, pp.149-155, 2011

Abstract : The aim of this work is to analyze a viscous flow in the axisymmetric nozzle taken into account the mesh size both in the free stream and into the boundary layer. The resolution of the Navier-Stokes equations is realized by using the finite volume method to determine the supersonic flow parameters at the exit of converging-diverging nozzle. The numerical technique uses the Flux Vector Splitting method of Van Leer. Here, adequate time stepping parameter, along with CFL coefficient and mesh size level is selected to ensure numerical convergence. The effect of the boundary layer thickness is significant at the exit of the nozzle. The best solution is obtained with using a very fine grid, especially near the wall, where we have a strong variation of velocity, temperature and shear stress. This study enabled us to confirm that the determination of boundary layer thickness can be obtained only if the size of the mesh is lower than a certain value limits given by our calculations. Les tuyères sont utilisées dans les bancs d’essais en vue d’obtenir des écoulements supersoniques pour différents tests. Elles aussi utilisées en propulsion pour obtenir les poussées nécessaire au déplacement des véhicules. The nozzles are used at the exit of the shock tube in order to obtain supersonic flows for various tests. They also used in propulsion to obtain the thrust necessary to the displacement of the vehicles.

Keyword : Supersonic flow, viscous flow, finite volume, nozzle