Particle tracking velocimetry in swirl-stabilised burners

Particle tracking velocimetry was applied in a water model of a swirl-stabilised burner and quantified Lagrangian particle residence time distributions in the near burner region and temporal evolution of particle mean square dispersion in axial and radial directions. The results suggest that instantaneous flow eddies with appropriate timescales increase particle response to the flow and “trap” particles within the time-averaged recirculation zone in the near burner region. Central particle injection doubled particle residence time up to the end of the internal recirculation zone relative to off-axis injection and this may lead to lower NOx emissions.