Results are presented of an experimental study consisting of two parts: 1) an investigation of the turbulent velocity fluctuation field in an isothermal boundary layer with homogeneous injection, and 2) a preliminary investigation of the turbulent velocity and temperature fluctuation fields in a boundary layer with both mass addition and combustion. The isothermal data indicate that the mean velocity profile with mass injection is well described by danger's universal velocity distribution when a pseudofriction velocity is defined using the maximum shear stress in the boundary layer. The turbulent intensities are increased significantly, and spectral measurements indicate that the additional energy is introduced at low wave numbers. As the mass addition rate increases, a progressively larger portion of the boundary layer tends to become isotropic in character, as though the interaction between the mean flow and the turbulence near the wall is damped by the blowing. Combustion measurements indicate that the turbulent intensity of the velocity fluctuation normal to the wall is approximately doubled near the wall, reflecting energy transfer from the combustion region to the turbulence. The spectral shapes obtained between the flame zone and the wall show distortion caused by combustion, as predicted by Eschenroeder.
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Wooldridge et al. (1966) studied this question.