Abstract
The DOE Co-Optima initiative focuses on investigating the ability of fuel properties to work in tandem with advanced combustion engines to increase fuel economy. One of the most promising advanced compression ignition strategies (ACI) is gasoline compression ignition (GCI). GCI leverages the relative auto-ignition resistance of gasoline-like fuels to enable highly premixed combustion processes at a range of air–fuel stratifications. In practical applications, engines must operate over a wide range of conditions, which associated with the inherent limitations and benefits of different ACI modes, suggests the engine should be capable of operating across multiple combustion modes. Operating the engine in multiple combustion modes effectively requires a fundamental understanding of fuel composition effects. The fact that GCI can operate with fuels designed for spark ignition engines enables the engine to be operated in either combustion mode when most suitable. This effort investigates the effects of fuel physical properties and aromatic content on GCI NOx, unburned hydrocarbons (HC), CO and particulate emissions. Three fuels with the same research octane number (RON) but different distillation curves and aromatic content are compared to isolate the impact of the two properties in a production, multi-cylinder engine. Different injection strategies targeting increasing levels of fuel stratification (100%, 70% and 0% premixed fuel) at a constant combustion phasing are utilized. Results showed that changes in fuel stratification had little impact on emissions of NOx, HC and CO until the fuel was injected completely near top dead center (TDC). Particulate sampling showed that the aromatic content of the fuel had greater impact on elemental carbon particulate matter (PM) emissions than the fuel distillation characteristics.
| Original language | English |
|---|---|
| Article number | 120893 |
| Journal | Fuel |
| Volume | 299 |
| DOIs | |
| State | Published - Sep 1 2021 |
Funding
This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ).Work by SWW was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This document was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor Lawrence Livermore National Security, LLC, nor any of their employees makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or Lawrence Livermore National Security, LLC. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or Lawrence Livermore National Security, LLC, and shall not be used for advertising or product endorsement purposes. This research was conducted as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) Bioenergy Technologies and Vehicle Technologies Offices. (Optional): Co-Optima is a collaborative project of multiple national laboratories initiated to simultaneously accelerate the introduction of affordable, scalable, and sustainable biofuels and high-efficiency, low-emission vehicle engines. The authors would gratefully like to thank the U.S. DOE Co-Optima Program Managers Kevin Stork and Alicia Lindauer for the support and guidance for this work.
| Funders | Funder number |
|---|---|
| Co-Optimization of Fuels & Engines | |
| U.S. Department of Energy | |
| Office of Energy Efficiency and Renewable Energy | |
| Lawrence Livermore National Laboratory | DE-AC52-07NA27344 |
Keywords
- Aromatic
- Combustion
- GCI
- Physical properties
- Soot
- particulate matter