Composite Spray Model for Augmentor Fuel Distribution Prediction

Augmentor static stability is critical to the operational performance of military systems that rely on gas turbine propulsion. Compared to early augmentor designs, the distance between the point of fuel injection and the reaction zone has become progressively shorter for modern augmentor designs, which can result in fuel droplets penetrating the reaction zone and variations in fuel jet penetration that can significantly impact the fuel distribution and in turn, engine stability. Highly-resolved modeling and simulation of fuel sprays is far too expensive for even the fastest of modern computers. In this project, we will develop a modeling technique that combines the Volume of Fluid method (VOF) with the Discrete Particle Method (DPM). We will take advantage of VOF’s ability to accurately describe the behavior of the spray in the dense region near the injector and marry it with the efficiency of the DPM method in regions of sparse droplet population far downstream of the injector. By combining the two methods in this fashion, we will greatly reduce the computational cost associated with accurate fuel spray modeling. We will utilize high-resolution VOF simulations as well as experimental data of a jet in cross-flow geometry to validate and benchmark our approach.