Predictions of Vortex Flow in a Diesel Multi-Hole Injector Using the RANS Modelling Approach

The occurrence of vortices in the sac volume automotive multi-hole fuel injectors plays an important role development vortex cavitation, which directly influences flow structure and emerging sprays that, turn, influence engine performance emissions. In this study, RANS-based turbulence modelling approach was used to predict internal a vertical axis-symmetrical (6) diesel injector under non-cavitating conditions. project aimed aforementioned vortical structures accurately at two different needle lifts order form correct opinion about their occurrence. accuracy simulations assessed by comparing predicted mean axial velocity RMS LDV measurements, showed good agreement. field analysis complex, 3D, with presence types nozzle hole. Two main were detected: “hole-to-hole” connecting vortex, double “counter-rotating” from wall entering hole facing it. Different patterns rotational direction have been observed low lift (anticlockwise) full (clockwise), due passages sac, causing much higher momentum inflow lower its narrower passage.