Pilot Ignition in Future Fuels in Engine Systems

Current and future engine emission regulations and the imminent need to decarbonize energy systems drive the development of future engine applications, capable of running on renewable fuels with efficient combustion mechanisms. In order to accomplish an optimized performance of future engines, predictive three-dimensional CFD simulations of the phenomena inside the combustion chamber provide a powerful and efficient tool to gain detailed insight into the characteristics of spray formation, mixture and ignition/combustion processes. The presented work demonstrates the application of a developed model implemented into a commercial CFD code to model ignition and combustion for pilot ignited dual fuel engine applications. Validation with experimental data from an optically accessible test rig allows the comparison of the simulation for mixture formation, ignition and combustion behaviour at engine relevant conditions. Excellent agreement between simulation and experiment was found for the application of pilot ignition of natural gas by micro n-dodecane sprays. Furthermore, the demonstration of the simulation of pilot ignition of ammonia is presented to showcase the flexibility of the developed numerical approach wrt. Fuel types, injection and engine parameters for the application in internal combustion engines.