Inscrição na biblioteca: Guest
TSFP DL Home Arquivos Comitê executivo

COMPRESSIBILITY EFFECTS IN A LARGE-EDDY SIMULATION OF A TURBULENT ROUND JET

Mohamed Maidi
Laboratoire des Ecoulements Céophysiques et Industriels(LEGI), BP 53, 38041 Grenoble Cedex 09, FRANCE

Marcel Lesieur
Equipe MoST / LEGI, B.P. 53, 38041 Grenoble Cedex 09, France

Gwenael Hauet
Laboratoire des Ecoulements Céophysiques et Industriels(LEGI), BP 53, 38041 Grenoble Cedex 09, FRANCE

Resumo

This paper presents an application of large-eddy simulations (LES) to spatially-developing compressible round jets. Our goal is to demonstrate the ability of LES to reproduce and analyze the influence of the Mach number on the spatial development of compressible round jets. For Mach number M = 0.9 and Reynolds number 36000 the numerical simulation is shown to be in good agreement with DNS of Freund (1999) and experimental data of Stromberg et al. (1980). We show that at Mach 0.7 and for two different Reynolds number values (Re = 2000,36000), the jet alternatively exhibits axisymmetric vortex structures (rings) and helical ones. Further downstream, they undergo alternate pairing as in the uniform-density case with the same upstream forcing. At M = 1.4 vortices are much more tilted in the flow direction, which is associated with an initail reduction of the jet spreading rate. Basic turbulent statistics and energy spectra are presented and assessed with respect to experiments.