2.4.2. Lagrangian Spray Modeling

The injection process in the current investigation has been modeled within a quiescent spray-chamber (7 bar pressure) in non-evaporative conditions (393.15 K). The domain is the same in all simulation cases and it is built on polar symmetry, where the nozzle axis is in the central position. In the near tip region, in all the tested cases, the mesh is built with the same resolution of the nozzle hole, and it gradually widens as the distance from the hole increases. The spray calculation is based on the Discrete Droplet Method (DDM); the k-ε turbulence closure for the RANS-equations solution has been adopted. The WAVE model [41] has been used to simulate the droplet secondary break-up process, assuming that the growth of an initial perturbation on a liquid surface is linked to its wavelength and to other physical and dynamic parameters of the injected fuel and the fluid domain. The particle interaction model based on the statistical approach proposed by O' Rourke [42] has been adopted.
