A Modeling Investigation into the Optimal Intake and Exhaust Valve Event Duration and Timing for a Homogenous Charge Compression Ignition Engine 2005-01-3746
Homogenous Charge Compression Ignition (HCCI) engine operation has been demonstrated using both residual trapping and residual re-induction. A number of production valve train technologies can accomplish either of these HCCI modes of operation. Wide-scale testing of the many valve timing and duration options for an HCCI engine is both time and cost prohibitive, thus a modeling study was pursued to investigate optimal HCCI valve-train designs using the geometry of a conventional gasoline Port-Fuel-Injected (PFI) Spark-Ignition (SI) engine. A commercially available engine simulation program (WAVE), as well as chemical kinetic combustion modeling tools were used to predict the best approaches to achieving combustion across a wide variety of valve event durations and timings. The results of this study are consistent with experimental results reported in the literature: both residual trapping and residual re-induction are possible strategies for HCCI combustion. The best valve timing strategies seem to be either very short intake and exhaust events (trapping), or short intake and long exhaust (re-induction). The effect of inlet air temperature on HCCI combustion with a residual trapping valve strategy was also investigated, and modeling suggests HCCI combustion is feasible even at low inlet air temperatures.
Citation: Rocafort, J., Andreae, M., Green, W., Cheng, W. et al., "A Modeling Investigation into the Optimal Intake and Exhaust Valve Event Duration and Timing for a Homogenous Charge Compression Ignition Engine," SAE Technical Paper 2005-01-3746, 2005, https://doi.org/10.4271/2005-01-3746. Download Citation
J. L. Chesa Rocafort, M. M. Andreae, W. H. Green, W. K. Cheng, Jim S. Cowart
Massachusetts Institute of Technology
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