Turbulent properties of a flat-plate boundary layer with a diffusion flame

An experimental investigation on a flat plate turbulent boundary layer with mass addition from a porous plate and diffusion flame has been made. Mean velocity and turbulent intensity of a fluctuating velocity parallel to the free streamwise direction (U bar and u prime) and a correlation of fluctuating velocities parallel and normal to the free stream-wise directional (UV bar) have been measured, using a laser-Doppler velocimeter. Hydrogen/nitrogen mixture was injected as a fuel from a porous plate. A free stream velocity was 10 m/s and the blowing mass ratio of mass injection and free air stream was 0.010. The profile of -uv bar corresponds to the profile of the mean velocity gradient normal to the free streamwise direction in the whole region except near the flame zone. These results suggest that the turbulence is an ordinary shear generated turbulence in the whole region of the boundary layer except near the flame zone. Near the flame zone, an influence of non-shear-generated turbulence on the profile of -uv bar is expected.