Numerical studies of air-assisted sprays

Simulations were made of sprays from a Ford Air-Assisted Fuel Injector to ascertain the importance of numerical and modeling issues. A previously developed injector model was implemented and appropriate boundary conditions were applied to an axisymmetric domain. Numerical studies were conducted to assess the effects of grid resolution, boundary placement, timestep size, and number of injected parcels. Modeling studies also showed that secondary droplet breakup and collision phenomena should not be neglected, and that the use of a multicomponent fuel produces spray images that are nearly identical to those of a single-component fuel. However, the furl vaporization of a multicomponent case is significantly different from that of a single-component case. These numerical and modeling studies established baseline simulations for a low- and a high-ambient pressure case (0.1 and 0.445 MPa, respectively), and the simulated spray images showed good agreement with experimental spray photographs of transient injection events from the Ford injector.