Abstract
At the beginning of the XXIst century, the Diesel engine has become a major actor for reducing both CO2 and pollutant emissions as well as fulfilling the customer requirements for driving pleasure. This success is undoubtedly due to the major improvements which have occurred on the whole combustion system with the direct injection. The fuel injection pressure increase associated to the multiple injection strategies has opened the way to optimise power and torque densities without any concession to noise and pollutant emissions . But these new technologies would have been largely unsuccessful without a minimum understanding of the complex physical phenomena present in the combustion chamber.
In the mean time, the 3D CFD simulation accuracy has been dramatically improved with the development of new spray and combustion models, for instance in Kiva code. More recently the Volume of Fluids (VoF) methodology has been applied to the internal flow in injector nozzles, taking into account the cavitation effects.
The aim of this paper is to show how these different CFD simulation tools associated to the Design of Experiments (DoE) could be more and more powerful for achieving quicker and safer engine developments. Some examples are given for up to date CR Diesel engines.