A 3D Eulerian Model to Improve the Primary Breakup of Atomizing Jet

A 3D Eulerian model has been developed to improve the primary break-up of an atomizing jet. The model is divided in three parts and is implemented in a modified version of KIVA II. The first part focuses mainly on the liquid dispersion, the second on the atomizing process itself, and the third on the adaptation of the model's mathematical formulation to the physics of the flow. Since the spray close to the injector is dense, an Eulerian formulation is thus chosen. However, when the spray is diluted, a Lagrangian formulation should then be applied. Different computations have been carried out using this new model and will be thoroughly discussed in this paper. The first calculation serves as a validation of the model. Those which follow demonstrate the importance of the internal liquid flow inside the injector on the spray development. They also manifest an influence of the air-co-flow, which assists the atomization of the spray. Last but not least, we observe the appropriate trends from the model when the pressure is increased inside the combustion chamber. The ensemble of these calculations displays the principal advantage of such a model, which enables us to follow the development of the spray upon entry into the combustion chamber, in other words, during the entire atomization process- both the primary break-up and after the secondary break-up. Beyond this point, no more initial cone angle nor initial droplet size distribution are further mandatory.