Aerodynamic Structure of a Laminar Boundary Layer Diffusion Flame over a Horizontal Flat Plate (2nd Report, Experimental Analysis)

Experimental investigations on an aerodynamic structure of a laminar boundary layer diffusion flame over a horizontal flat plate have been performed. Effects of gravitational force and velocity gradient of free stream velocity have been discussed. When a fuel (methane) is injected upward, the velocity around a flame zone is locally accelerated, and the velocity gradient at the wall is increased as compared with that of isothermal flow. On the other hand, when a fuel is injected downward, the velocity is retarded, and the velocity gradient at the wall is decreased in not only a downstream region of the leading flame edge but also the upstream region. This reveals that the gravitational force varies the local pressure distribution not only in a downstream region of the leading flame edge but also in the upstream region. It is also elucidated that the velocity gradient of free steam velocity varies the velocity profiles in a boundary layer.