Dependence of Flow Characteristics of a High Performance S.I. Engine Intake System on Test Pressure and Tumble Generation Conditions - Part2: Numerical Analysis.

The design of new geometries of combustion chambers together with the design of improved intake systems are some of the most important applied research activities that attempt to improve the complex processes underlying combustion. The design and the analysis of new optimized geometries which use numerical simulations, based on a commercial CFD code utilization, seems to be a very interesting way to reduce the industrial costs in the engines developing activity. In the present work, steady state simulations of an intake system of a race engine head of Ducati Corse, using a commercial 3D-CFD code, are carried out to tune the parameters of the used models and to analyze different configurations. The models validation is based on the experimental results obtained from a parallel paper concerning the Tumble Coefficient (Nt) and the Discharge Coefficient (Cd) obtained using two configurations: with an L-shaped tumble adaptor and a standard one. A limited sensitivity analysis of the Cd and Nt tumble coefficient from the pressure boundary conditions is also carried out.