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

Title: Insights into engine autoignition: Combining engine thermodynamic trajectory and fuel ignition delay iso-contour

Abstract

One of the ultimate goals of chemical kinetic study is to understand and predict autoignition in engines. In this study, utilizing toluene primary reference fuels (TPRF) as a gasoline surrogate and a recently developed multicomponent gasoline kinetic mechanism, we have demonstrated a general approach to analyze autoignition in arbitrary spark-ignition (SI) and advanced compression ignition (ACI) engine conditions by combining thermodynamic pressure-temperature trajectory and the fuel ignition delay iso-contours. This method allows direct evaluation of controlling chemistry, potential involvement of low temperature heat release, and the dependence of autoignition to conventional fuel metrics (research and motor octane rating, i.e., RON and MON, and octane sensitivity OS = RON-MON) and engine operating conditions such as equivalence ratio, exhaust gas recirculation (EGR) ratio and engine intake conditions. Applying the analysis to the pressure-temperature trajectories of the conventional RON and MON tests, as well as those beyond RON and beyond MON, distinct roles of conventional gasoline fuel metrics and engine operating parameters are identified for all representative engine conditions. By comparing the autoignition behavior in ACI and SI engine conditions, the knowledge obtained from SI engine knock cannot be directly transferred to ACI bulk combustion phasing control in general, due to the differentmore » mixture equivalence ratios and the associated differences in reactivity and its dependence. Furthermore, this method could be extended to generate an auto-ignition map for arbitrary fuels and arbitrary engine trajectories, and the useful insights and overall evaluations can be used to complement conventional kinetic simulation of engine cycles.« less

Authors:
 [1]; ORCiD logo [1]; ORCiD logo [2];  [3]; ORCiD logo [4]
  1. Oakland Univ., Rochester, MI (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Univ. of Illinois at Chicago, Chicago, IL (United States)
  4. Texas Tech Univ., Lubbock, TX (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1484991
Grant/Contract Number:  
AC05-00OR22725
Resource Type:
Accepted Manuscript
Journal Name:
Combustion and Flame
Additional Journal Information:
Journal Volume: 200; Journal Issue: C; Journal ID: ISSN 0010-2180
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
33 ADVANCED PROPULSION SYSTEMS; Autoignition; Advanced compression ignition (ACI); Octane rating; Octane sensitivity; Livengood-Wu method; Phi-sensitivity

Citation Formats

Tao, Mingyuan, Zhao, Peng, Szybist, James P., Lynch, Patrick, and Ge, Haiwen. Insights into engine autoignition: Combining engine thermodynamic trajectory and fuel ignition delay iso-contour. United States: N. p., 2018. Web. doi:10.1016/j.combustflame.2018.11.025.
Tao, Mingyuan, Zhao, Peng, Szybist, James P., Lynch, Patrick, & Ge, Haiwen. Insights into engine autoignition: Combining engine thermodynamic trajectory and fuel ignition delay iso-contour. United States. doi:10.1016/j.combustflame.2018.11.025.
Tao, Mingyuan, Zhao, Peng, Szybist, James P., Lynch, Patrick, and Ge, Haiwen. Tue . "Insights into engine autoignition: Combining engine thermodynamic trajectory and fuel ignition delay iso-contour". United States. doi:10.1016/j.combustflame.2018.11.025. https://www.osti.gov/servlets/purl/1484991.
@article{osti_1484991,
title = {Insights into engine autoignition: Combining engine thermodynamic trajectory and fuel ignition delay iso-contour},
author = {Tao, Mingyuan and Zhao, Peng and Szybist, James P. and Lynch, Patrick and Ge, Haiwen},
abstractNote = {One of the ultimate goals of chemical kinetic study is to understand and predict autoignition in engines. In this study, utilizing toluene primary reference fuels (TPRF) as a gasoline surrogate and a recently developed multicomponent gasoline kinetic mechanism, we have demonstrated a general approach to analyze autoignition in arbitrary spark-ignition (SI) and advanced compression ignition (ACI) engine conditions by combining thermodynamic pressure-temperature trajectory and the fuel ignition delay iso-contours. This method allows direct evaluation of controlling chemistry, potential involvement of low temperature heat release, and the dependence of autoignition to conventional fuel metrics (research and motor octane rating, i.e., RON and MON, and octane sensitivity OS = RON-MON) and engine operating conditions such as equivalence ratio, exhaust gas recirculation (EGR) ratio and engine intake conditions. Applying the analysis to the pressure-temperature trajectories of the conventional RON and MON tests, as well as those beyond RON and beyond MON, distinct roles of conventional gasoline fuel metrics and engine operating parameters are identified for all representative engine conditions. By comparing the autoignition behavior in ACI and SI engine conditions, the knowledge obtained from SI engine knock cannot be directly transferred to ACI bulk combustion phasing control in general, due to the different mixture equivalence ratios and the associated differences in reactivity and its dependence. Furthermore, this method could be extended to generate an auto-ignition map for arbitrary fuels and arbitrary engine trajectories, and the useful insights and overall evaluations can be used to complement conventional kinetic simulation of engine cycles.},
doi = {10.1016/j.combustflame.2018.11.025},
journal = {Combustion and Flame},
number = C,
volume = 200,
place = {United States},
year = {2018},
month = {12}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

Figures / Tables:

Fig. 1 Fig. 1: Composition of TPRF fuels (a). with the same RON = 95, but different OS from 0 to 9, (b). with the same OS = 8.5, but different RON from 87 to 96.8.

Save / Share: