Numerical Simulation Of Primary Atomization Of Swirling Liquid Sheet Using Transforming Algorithm

Fuel atomization is of significant importance to the combustion performance in propelling systems of aeronautic and astronautic engines. The atomization of swirling liquid sheet which is commonly seen in fuel injectors is studied numerically in detail in this paper. Adaptive mesh refinement with the quadtree/octree grid structure is applied to refine the grids where the higher resolution is required such as gasliquid interfaces. A transforming algorithm is developed to transform the Eulerian droplets whose sizes are comparable to the grid resolution into the Lagrangian particles. The Lagrangian particles are tracked with the dynamic drag model and transformed back into the Eulerian droplets when they move close to the resolved liquid structures. This simulation strategy reduces the computational errors in capturing interface shapes and provides a more realistic initial condition for the simulation of secondary atomization. The algorithm is verified and applied to simulate the primary atomization of swirling liquid sheet under different conditions. The mechanism behind the atomization process is studied through clear information of the flow field. Atomization characteristics and the information for droplets are also analyzed and compared under different conditions.