skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Characterization of temporal variations and feedback timescales of exhaust gas recirculation gas properties using high-speed diode laser absorption spectroscopy for next-cycle control of cyclic variability

Journal Article · · International Journal of Engine Research
 [1]; ORCiD logo [1]
  1. Oak Ridge National Laboratory, MS6472 Oak Ridge, TN, USA
+ Show Author Affiliations

Dilute combustion offers efficiency gains in boosted gasoline direct injection engines both through knock-limit extension and thermodynamic advantages (i.e. the effect of γ on cycle efficiency), but is limited by cyclic variability at high dilution levels. Past studies have shown that the cycle-to-cycle dynamics are a combination of deterministic and stochastic effects. The deterministic causes of cyclic variations, which arise from feedback due to exhaust gas recirculation, imply the possibility of using active control strategies for dilution limit extension. While internal exhaust gas recirculation will largely provide a next-cycle effect (short-timescale feedback), the feedback of external exhaust gas recirculation will have an effect after a delay of several cycles (long timescale). Therefore, control strategies aiming to improve engine stability at dilution limit may have to account for both short- and long-timescale feedback pathways. This study shows the results of a study examining the extent to which variations in exhaust gas recirculation composition are preserved along the exhaust gas recirculation flow path and thus the relative importance and information content of the long-timescale feedback pathway. To characterize the filtering or retention of cycle-resolved feedback information, high-speed (1–5 kHz) CO 2 concentration measurements were performed simultaneously at three different locations along the low-pressure external exhaust gas recirculation loop of a four-cylinder General Motors gasoline direct injection engine using a multiplexed two-color diode laser absorption spectroscopy sensor system during steady-state and transient engine operation at various exhaust gas recirculation levels. It was determined that cycle-resolved feedback propagates through internal residual gases but is filtered out by the low-pressure exhaust gas recirculation flow system and do not reach the intake manifold. Intermediate variations driven by flow rate and compositional changes are also distinguished and identified.

Research Organization:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Grant/Contract Number:
AC05-00OR22725
OSTI ID:
1564276
Alternate ID(s):
OSTI ID: 1528737
Journal Information:
International Journal of Engine Research, Journal Name: International Journal of Engine Research Vol. 20 Journal Issue: 8-9; ISSN 1468-0874
Publisher:
SAGE PublicationsCopyright Statement
Country of Publication:
United Kingdom
Language:
English
Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

References (15)

The Interaction between Fuel Anti-Knock Index and Reformation Ratio in an Engine Equipped with Dedicated EGR journal April 2016
Prior-Cycle Effects in Lean Spark Ignition Combustion - Fuel/Air Charge Considerations conference February 1998
Analysis of Cyclic Variability of Heat Release for High-EGR GDI Engine Operation with Observations on Implications for Effective Control journal April 2013
Effects of External EGR Loop on Cycle-to-Cycle Dynamics of Dilute SI Combustion journal April 2014
Simultaneous high-speed gas property measurements at the exhaust gas recirculation cooler exit and at the turbocharger inlet of a multicylinder diesel engine using diode-laser-absorption spectroscopy journal January 2015
Synergies between High EGR Operation and GDI Systems journal April 2008
Invited Review: A review of deterministic effects in cyclic variability of internal combustion engines journal February 2015
The Reduced Effectiveness of EGR to Mitigate Knock at High Loads in Boosted SI Engines journal February 2017
An assessment of thermodynamic merits for current and potential future engine operating strategies journal February 2017
Characterization of lean combustion instability in premixed charge spark ignition engines journal August 2000
A Simple Model for Cyclic Variations in a Spark-Ignition Engine
  • Daw, C. S.; Finney, C. E. A.; Green, J. B.
  • 1996 SAE International Fall Fuels and Lubricants Meeting and Exhibition, SAE Technical Paper Series https://doi.org/10.4271/962086
conference October 1996
High-speed diode laser measurements of temperature and water vapor concentration in the intake manifold of a diesel engine journal January 2014
Mapping of exhaust gas recirculation and combustion-residual backflow in the intake ports of a heavy-duty diesel engine using a multiplexed multi-species absorption spectroscopy sensor journal July 2017
Experimental Investigation of the Initial Stages of Flame Propagation in a Spark-Ignition Engine: Effects of Fuel, Hydrogen Addition and Nitrogen Dilution journal May 2010
Design and development of a probe-based multiplexed multi-species absorption spectroscopy sensor for characterizing transient gas-parameter distributions in the intake systems of I.C. engines journal March 2017

Similar Records

Related Subjects

Dilute combustion
cyclic variability
nonlinear dynamics
exhaust gas recirculation
combustion stability