Study of compressible turbulent flows in supersonic environment by large-eddy simulation

Hybrid numerical scheme;Compressible turbulence;LDKM closure

Genin, Franklin Marie ; Aerospace Engineering

University:Georgia Institute of Technology

Department:Aerospace Engineering

关键词: Hybrid numerical scheme;    Compressible turbulence;    LDKM closure;   

Others  :  https://smartech.gatech.edu/bitstream/1853/28085/1/genin_franklin_m_200905_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

A Large-Eddy Simulation (LES) methodology adapted to the resolution of high Reynolds number turbulent flows in supersonic conditions was proposed and developed. A novel numerical scheme was designed, that switches from a low-dissipationcentral scheme for turbulence resolution to a flux difference splitting scheme in regionsof discontinuities. Furthermore, a state-of-the-art closure model was extended in orderto take compressibility effects and the action of shock / turbulence interaction into account.The proposed method was validated against fundamental studies of high speed flows and shock / turbulence interaction studies. This new LES approach was employed for the study of shock / turbulent shear layer interaction as a mixing-augmentation technique, and highlighted the efficiency in mixing improvement after the interaction, but also the limited spatial extent of this turbulent enhancement. A second practicalstudy was conducted by simulating the injection of a sonic jet normally to a supersonic crossflow. The validity of the simulation was assessed by comparison with experimentaldata, and the dynamics of the interaction was examined. The sources of vortical structures were identified, with a particular emphasis on the impact of the flow speed onto the vortical evolution.