VALIDATION OF A MULTICOMPONENT FUEL SPRAY MODEL FOR GASOLINE DIRECT INJECTION ENGINE CONDITIONS AND STUDY ON INFLUENCE OF RESOLVING THE COUNTERBORE INJECTOR

Artikel i vetenskaplig tidskrift, 2022

When simulating fuel sprays in gasoline direct injection (GDI) engines, few studies have investigated resolving the counterbore and how this may influence spray predictions. In this work, we used the stochastic blob and bubble (VSB2) spray model to conduct simulations where fuel was injected into a constant volume combustion vessel. The counterbore was resolved both radially and axially. In addition, the injector orifice was resolved into nine cells. The boundary conditions were the same as the engine combustion network (ECN) noncombusting case for multicomponent Spray G (G1, E00 case in ECN, Spray G). Results obtained using two simulation meshes were compared to experimental data: (1) without resolving the counterbore and (2) with resolved counterbore. Both meshes predicted the experimental liquid and vapor penetration lengths reasonably well and the differences in the penetration lengths between the two meshes were insignificant. However, a clear difference was detected in the fuel-air mixing (quantified by the mixing rate) and maximum values of k and epsilon. There were also noticeable differences between the two meshes in the peak fuel vapor fractions of the two most volatile components.