Combustion of Solid-Fuel Slabs Containing Boron Particles in Step Combustor

The combustion processes of solid fuel slabs with and without boron particle addition were investigated in a planar step combustor. The study was performed under conditions of air inlet velocity and temperature relevant to ramjet applications. The highly turbulent, multiphase combustion process has been analyzed with various intrusive and non-intrusive diagnostic techniques. Gas phase temperature distributions and particle velocities as well as concentrations of various stable reaction products have been determined in order to show the movement and the combustion of the reacting particle phase in the recirculation zone and the downstream boundary layer with the embedded reaction zone. Large scale, coherent vortex structures were observed. These structures exist predominantly in the region above the hydrocarbon diffusion flame located inside the developing boundary layer and show an intense and highly turbulent mixing process. The results show dependencies of the energy release on the flow field related to the presence of reacting or non-reacting particles.

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