Direct numerical simulations are conducted to investigate the effect of turbulence-radiation interaction in hypersonic turbulent boundary layers, representative of the Orion crew exploration vehicle at the peak heating condition during reentry. Both the effects of emission and absorption are considered by solving the radiative transfer equation using the tangent slab approximation and a spectral model with line-by-line accuracy. Nondimensional governing parameters to measure the significance of turbulence-radiation interaction are proposed, and the direct numerical simulation fields with and without radiation coupling are used to assess turbulence-radiation interaction. Is it found that the fluid medium within the boundary layer is optically thick with local emission largely counterbalanced by the absorbed irradiation, which results in much weaker overall radiative source termr- qR, and the thermal radiation has minimal backward influence on the turbulence flowfield. In addition, both the uncoupled and coupled results show that there is no sizable interaction between turbulence and radiation at the hypersonic environment under investigation. An explanation for small turbulence-radiation interaction intensity is also provided.
ASJC Scopus subject areas
- Aerospace Engineering