Abstract
In the present paper, a computational study has been performed in order to clarify the effects of the needle eccentricity in a real multihole microsac nozzle. This nozzle has been simulated at typical operating conditions of a diesel engine, paying special attention to the internal flow development and cavitation appearance within the discharge orifices. For that purpose, a multiphase flowsolver based on a homogeneous
equilibrium model with a barotropic equation of state has been used, introducing the turbulence effects by Reynolds-averaged NavierStokes methods with a re-normalization group k-eps model. The results obtained from this investigation have demonstrated the huge influence of the needle position on the flow characteristics, showing important hole to hole differences.