Effects of External EGR Loop on Cycle-to-Cycle Dynamics of Dilute SI Combustion
Conference
·
OSTI ID:1127380
- ORNL
Operation of spark-ignition (SI) engines with high levels of charge dilution through exhaust gas recirculation (EGR) achieves significant efficiency gains while maintaining stoichiometric operation for compatibility with three-way catalysts. Dilution levels, however, are limited by cyclic variability including significant numbers of misfires that becomes significant with increasing dilution. This variability has been shown to have both stochastic and deterministic components. Stochastic effects include turbulence, mixing variations, and the like, while the deterministic effect is primarily due to the nonlinear dependence of flame propagation rates and ignition characteristics on the charge composition, which is influenced by the composition of residual gases from prior cycles. The dynamics of operation with an external EGR loop differ substantially from those of dilute operation without external recirculation, both in time-scale and cylinder synchronization effects, especially when misfires are encountered. This paper examines these differences and the implications for prior-cycle-based control strategies.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Fuels, Engines and Emissions Research Center; National Transportation Research Center (NTRC)
- Sponsoring Organization:
- EE USDOE - Office of Energy Efficiency and Renewable Energy (EE)
- DOE Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1127380
- Country of Publication:
- United States
- Language:
- English
Similar Records
Impact of delayed spark restrike on the dynamics of cyclic variability in dilute SI combustion
Analysis of Cyclic Variability of Heat Release for High-EGR GDI Engine Operation with Observations on Implications for Effective Control
CHARACTERISTICS OF CYCLE-TO-CYCLE COMBUSTION VARIABILITY AT PARTIAL-BURN LIMITED AND MISFIRE LIMITED SPARK TIMING UNDER HIGHLY DILUTED CONDITIONS
Conference
·
Thu Dec 31 23:00:00 EST 2015
·
OSTI ID:1255662
Analysis of Cyclic Variability of Heat Release for High-EGR GDI Engine Operation with Observations on Implications for Effective Control
Conference
·
Mon Dec 31 23:00:00 EST 2012
·
OSTI ID:1082011
CHARACTERISTICS OF CYCLE-TO-CYCLE COMBUSTION VARIABILITY AT PARTIAL-BURN LIMITED AND MISFIRE LIMITED SPARK TIMING UNDER HIGHLY DILUTED CONDITIONS
Conference
·
Tue Dec 31 23:00:00 EST 2019
·
OSTI ID:1632182