Droplet size distribution effects in an edge flame with a fuel spray

The impact of the initial droplet size distribution on the behavior of an edge flame formed in the mixing layer of laminar co-flowing streams of oxidant and a spray of liquid fuel initially separated by a splitter plate is investigated for the first time. The spray is modeled using the sectional approach, and three quite different size distributions are considered having a common Sauter Mean Diameter (SMD). The nonlinear governing equations are formulated within the thermal-diffusional framework, and solved using finite differences. A parametric study discloses that despite having the same SMD the actual initial droplet size distribution influences flame location, maximum reaction rate and temperature. But more critically it can be destabilizing and lead to flame oscillations, depending on the actual initial size distribution used.