Numerical study of the hydrogen/air mixing in a high performance 2 stroke opposed piston engine

Hydrogen as a fuel for internal combustion engines is the most promising candidate for the achievement of the zero-emissions target fixed by the European institutions for sport-cars application. The development of a high specific power hydrogen engines is not trivial considering the low volumetric energy density of hydrogen. Furthermore, the necessity to reduce the engine encumbrance in favour of fuel on-board storage makes particularly attractive alternative engine architecture such as the 2 stoke opposed piston one. A numerical study is carried out to numerically evaluate the potential of such architecture finding in hydrogen/air mixing a critical aspect to be optimized for the achievement of the performance target. An extensive 3D-CFD study is performed analysing the impact on mixture formation and combustion evolution/efficiency of the hydrogen injector location, orientation and injection phasing with the final aim to define design guidelines for the development of this new engine technology. To improve the mixture homogeneity an innovative multi-point injection strategy is also designed, virtually implemented and tested.