An Interactively Coupled CFD-Multi-Zone Approach to Model HCCI Combustion

The objective of this work is to present an innovative interactively coupled CFD-multi-zone approach. In a consistent manner, the approach combines detailed flow field information obtained from CFD with detailed chemical kinetics solved in a multi-zone model. Combustion and pollutant formation in an HCCI engine with recompressing VVA strategy are numerically investigated using the interactively coupled CFD-multi-zone approach. A surrogate fuel for gasoline is used in the simulation that consists of n-heptane (18% liquid volume fraction) and isooctane (82% liquid volume fraction). The underlying complete reaction mechanism comprises 482 elementary reactions and 115 chemical species. The interactively coupled CFD-multi-zone approach shows to be accurate enough to describe HCCI chemistry, and is at the same time economical enough to allow application in an industrial environment. For the test case investigated, the simulation results are compared to experimental data that has been obtained using real gasoline. The overall agreement between simulation and experiment is found to be very good.