Samso - Tr - 70 - 44 ! ' Co Radiation from Air - Teflon Boundary Layers

Rcicliation profiles in an ablating flat plate Air-Teflon laminar boundary layer have been studied both experimentally and theoretically. The experiments were conducted in a one atmosphere, 3000 60U0 K, subsonic free stream produced by an arc jet. Spatially resolved radiation profiles within the boundary layer were obtained in both the visible and near infrared. Spatially integrated boundary layer radiation was measured in the 4 • 10|| region. The major radiation in the visible and near ultraviolet wavelengths was the CN violet. In the infrared, the major radiators were CO, CO?, NO and COF.,. The theory which was developed to predict the structure included coupling of the heat and mass transfer at the Teflon surface. A "partial equilibrium" model for the Teflon-air chemistry was utilized, which does not allow the formation of CF, and CF. within the boundary layer. For the selected wavelengths in the infrared the theory generally predicted quite well both the spatial location and magnitude of the peak radiation, and also predicted the integrated radiation across the layer to within a factor of two. For the selected wavelength in the visible, the radiation intensity, which commt from CN, is much larger than predicted, indicating that the CN is not in thrmiodynamic equilibrium.