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Title: Isolating the effects of reactivity stratification in reactivity-controlled compression ignition with iso-octane and n-heptane on a light-duty multi-cylinder engine

Journal Article · · International Journal of Engine Research
 [1];  [1];  [2];  [2];  [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
  3. Univ. d'Orleans, Orleans (France)
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Reactivity-controlled compression ignition (RCCI) is a dual-fuel variant of low-temperature combustion that uses in-cylinder fuel stratification to control the rate of reactions occurring during combustion. Using fuels of varying reactivity (autoignition propensity), gradients of reactivity can be established within the charge, allowing for control over combustion phasing and duration for high efficiency while achieving low NOx and soot emissions. In practice, this is typically accomplished by premixing a low-reactivity fuel, such as gasoline, with early port or direct injection, and by direct injecting a high-reactivity fuel, such as diesel, at an intermediate timing before top dead center. Both the relative quantity and the timing of the injection(s) of high-reactivity fuel can be used to tailor the combustion process and thereby the efficiency and emissions under RCCI. While many combinations of high- and low-reactivity fuels have been successfully demonstrated to enable RCCI, there is a lack of fundamental understanding of what properties, chemical or physical, are most important or desirable for extending operation to both lower and higher loads and reducing emissions of unreacted fuel and CO. This is partly due to the fact that important variables such as temperature, equivalence ratio, and reactivity change simultaneously in both a local and a global sense with changes in the injection of the high-reactivity fuel. This study uses primary reference fuels iso-octane and n-heptane, which have similar physical properties but much different autoignition properties, to create both external and in-cylinder fuel blends that allow for the effects of reactivity stratification to be isolated and quantified. This study is part of a collaborative effort with researchers at Sandia National Laboratories who are investigating the same fuels and conditions of interest in an optical engine. Furthermore, this collaboration aims to improve our fundamental understanding of what fuel properties are required to further develop advanced combustion modes.

Research Organization:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Sustainable Transportation Office. Vehicle Technologies Office
Grant/Contract Number:
AC04-94AL85000
OSTI ID:
1399570
Report Number(s):
SAND-2017-9444J; 656713
Journal Information:
International Journal of Engine Research, Vol. 19, Issue 9; ISSN 1468-0874
Publisher:
SAGECopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 18 works
Citation information provided by
Web of Science

References (21)

Progress and recent trends in reactivity-controlled compression ignition engines journal July 2015
Compendium of Experimental Cetane Numbers report August 2014
Analysis of the Impact of Selected Fuel Thermochemical Properties on Internal Combustion Engine Efficiency journal December 2011
Reactivity Controlled Compression Ignition Drive Cycle Emissions and Fuel Economy Estimations Using Vehicle Systems Simulations with E30 and ULSD journal April 2014
Characterization of Reactivity Controlled Compression Ignition (RCCI) Using Premixed Gasoline and Direct-Injected Gasoline with a Cetane Improver on a Multi-Cylinder Engine journal January 2015
Density and Viscosity Measurements of 2,2,4-Trimethylpentane (Isooctane) from 198 K to 348 K and up to 100 MPa journal January 1996
The Effects of Charge Preparation, Fuel Stratification, and Premixed Fuel Chemistry on Reactivity Controlled Compression Ignition (RCCI) Combustion journal February 2017
Investigation of Fuel Reactivity Stratification for Controlling PCI Heat-Release Rates Using High-Speed Chemiluminescence Imaging and Fuel Tracer Fluorescence journal January 2012
RCCI Combustion Regime Transitions in a Single-Cylinder Optical Engine and a Multi-Cylinder Metal Engine journal February 2017
Effect of Premixed Fuel Preparation for Partially Premixed Combustion With a Low Octane Gasoline on a Light-Duty Multicylinder Compression Ignition Engine journal November 2015
Effect of Piston Bowl Geometry on Dual Fuel Reactivity Controlled Compression Ignition (RCCI) in a Light-Duty Engine Operated with Gasoline/Diesel and Methanol/Diesel journal April 2013
Heavy-Duty RCCI Operation Using Natural Gas and Diesel journal January 2012
Clean combustion enabling with ethanol on a dual-fuel compression ignition engine journal March 2015
Densities, viscosities, refractive indices, and surface tensions for binary and ternary mixtures of 2-propanol, tetrahydropyran, and 2,2,4-trimethylpentane journal February 2011
Boosted HCCI - Controlling Pressure-Rise Rates for Performance Improvements using Partial Fuel Stratification with Conventional Gasoline journal April 2011
Surface Tension of Heptane, Decane, Hexadecane, Eicosane, and Some of Their Binary Mixtures journal September 2002
The Contribution of Lubricant to the Formation of Particulate Matter with Reactivity Controlled Compression Ignition in Light-Duty Diesel Engines journal December 2014
Comparison of Compression Ignition Engine Noise Metrics in Low-Temperature Combustion Regimes journal April 2013
Fuel reactivity controlled compression ignition (RCCI): a pathway to controlled high-efficiency clean combustion journal June 2011
Review of high efficiency and clean reactivity controlled compression ignition (RCCI) combustion in internal combustion engines journal February 2015
A perspective on the range of gasoline compression ignition combustion strategies for high engine efficiency and low NOx and soot emissions: Effects of in-cylinder fuel stratification journal July 2016

Cited By (2)

Impacts of Air-Fuel Stratification in ACI Combustion on Particulate Matter and Gaseous Emissions journal May 2019
Multi-objective optimizations of the boot injection strategy for reactivity controlled compression ignition engines journal August 2018

Figures / Tables (34)

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