Abstract
The fuel spray of automobile engine includes multi-scale free surfaces; a liquid film forms at the fuel injector outlet, and then the liquid film breaks up into droplets. To simulate multi-scale free surfaces, we combined a particle method and a Cartesian grid method. The liquid film breakup near the injector outlet was simulated using the particle method, and the air/fuel mixture after the liquid film breakup was simulated using the Cartesian grid method. Distributions of droplet diameters and velocities, calculated in liquid-film breakup simulation, were used as an initial condition of spray for the Cartesian grid method. We applied our new method to simulate a collision fuel injector. The simulation results were compared with the measurements. The liquid film breakup near the injector outlet and the behavior of the air/fuel mixture qualitatively agreed with the measurements.
