Temperature Fluctuation Scaling in Reacting Boundary Layers
نویسندگان
چکیده
The direct numerical simulation (DNS) data of a turbulent, reacting boundary layer is used to study the turbulence-chemistry interaction and the scaling of the temperature fluctuations. We find that there is a feedback between the turbulence and the chemical reactions. Temperature fluctuations increase the reaction rates. Endothermic reactions reduce the magnitude of the temperature fluctuations. However, the turbulent boundary layer is self-sustained and the magnitude of the temperature fluctuations is maintained. Exothermic reactions increase the magnitude of the temperature fluctuations. The reactions cause localized compressions and expansions that feed the turbulent kinetic energy. The evolution equations for the turbulent energy show that the feedback takes place through the transport and production terms. The data reveals a physically consistent relation between the temperature variance and the mean flow parameters. These results are consistent with those previously found in reacting isotropic turbulence.
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