Abstract
The Homogeneous Charge Compression Ignition (HCCI) is still a promising concept to optimize internal combustion (IC) engines with respect to emissions. The cycle-to-cycle variations of in-cylinder flow play an important role in HCCI combustion processes and can result in combustion instability due to the lean as well as knock combustion conditions. In order to characterize mentioned above effects, the Large Eddy Simulation (LES) has proved to be a reliable method. Multi-cycle LES based analysis has been carried out on a motored engine configuration to characterize the unsteady effects of HCCI combustion processes for both fully premixed mixture and early-direct spray injection cases. In-cylinder pressure and temperature as a function of crank angle were analyzed in terms of mean and standard deviation.
