Numerical Investigation of Spray Collapse in GDI with OpenFOAM

During certain operating conditions in spark-ignited direct injection engines (GDI), the injected fuel will be superheated and begin to rapidly vaporize. Fast vaporization can beneficial for fuel–oxidizer mixing subsequent combustion, but it poses risk of spray collapse. In this work, collapse is numerically investigated a single hole G eight-hole injector an engine combustion network (ECN). Results from new OpenFOAM solver are first compared against results commercial CONVERGE software single-hole injectors validated. The corroborate perception that superheat ratio Rp, which typically used classification flashing regimes, cannot describe behavior. Three cases using geometry with experimental data. case standard G2 test case, iso-octane as fluid, only slightly superheated, whereas two other use propane show behavior experiment. numerical support assumption interaction shocks due underexpanded vapor jet causes Further, structures match well data, shock interactions provide explanation observed phenomenon discussed.