Subgrid-scale model for the temperature fluctuations in reacting hypersonic turbulent flows
نویسندگان
چکیده
A direct numerical simulation ~DNS! database is used to develop a model of subgrid-scale temperature fluctuations for use in large-eddy simulations of turbulent, reacting hypersonic flows. The proposed model uses a probability density representation of the temperature fluctuations. The DNS database reveals a physically consistent relation between the resolved-scale flow conditions that may be used to predict the standard deviation of the Gaussian probability density function ~PDF!. The model is calibrated and tested by comparison to simulations of decaying isotropic turbulence. The conditional single-variable PDF model is found to capture the fluctuations in temperature and product formation. © 1999 American Institute of Physics. @S1070-6631~99!01909-1#
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