Experimental study of a model gas turbine combustor swirl cup. Part I - Two-phase characterization

Abstract

The behavior of droplets and the continuous phase (i.e., gas in the presence of the droplets) downstream of a 3 x model gas turbine combustor dome swirl cup is characterized via phase Doppler interferometry in the absence of reaction. The goal is to improve the understanding of droplet-gas interaction in a complex flow typical of that produced by engine hardware. Three components of continuous phase and droplet velocities were measured along with droplet size. The measurements reveal that (1) at the exit plane of the swirl cup, more uniform and finer droplets are produced relative to the atomizer alone, (2) both the continuous phase and droplets recirculate, (3) the region downstream of the swirl cup into which droplets join the recirculation is correlated with droplet size, and (4) significant slip velocities exist between the continuous phase and the droplets which are also correlated with droplet size and reflect a strong momentum exchange between the phases. 11 refs.