Simulation of turbulent hypersonic flows : subgrid-scale model for the temperature fluctuations in reacting turbulence /

Direct numerical simulations of turbulent reacting flows were performed to study the interaction between chemical heat release and turbulent fluid motion. A portion of the energy released by exothermic reactions is placed in the compressible mode of turbulent kinetic energy, with very little energy disposed to the incompressible mode. This process results in a positive feedback mechanism, whereby temperature fluctuations are amplified by the chemical reactions. In the case of endothermic reactions, the feedback is negative, resulting in decreased turbulent motion. The results of the simulations were used to develop a model for temperature fluctuations under conditions typical of a hypersonic boundary layer. This model has been validated and is suitable for use in the large eddy simulation of hypersonic turbulent boundary layers.Photocopy."Final Report : 1 Jun 1996 -- 30 Sep 1997.""31 Dec 1997."Includes bibliographical references.Direct numerical simulations of turbulent reacting flows were performed to study the interaction between chemical heat release and turbulent fluid motion. A portion of the energy released by exothermic reactions is placed in the compressible mode of turbulent kinetic energy, with very little energy disposed to the incompressible mode. This process results in a positive feedback mechanism, whereby temperature fluctuations are amplified by the chemical reactions. In the case of endothermic reactions, the feedback is negative, resulting in decreased turbulent motion. The results of the simulations were used to develop a model for temperature fluctuations under conditions typical of a hypersonic boundary layer. This model has been validated and is suitable for use in the large eddy simulation of hypersonic turbulent boundary layers.Report prepared by University of Minnesota, Aerospace Engineering and Mechanics, Minneapolis, Minnesota, under contract no.Mode of access: Internet