Abstract
Experimental work on reactivity-controlled compression ignition (RCCI) in a small-bore, multi-cylinder engine operating on premixed iso-octane and direct-injected n-heptane has shown an unexpected combustion phasing advance at early injection timings, which has not been observed in large-bore engines operating under RCCI at similar conditions. In this work, computational fluid dynamics (CFD) simulations were performed to investigate whether spray-wall interactions could be responsible for this result. Comparison of the spray penetration, fuel film mass, and in-cylinder visualization of the spray from the CFD results to the experimentally measured combustion phasing and emissions provided compelling evidence of strong fuel impingement at injection timings earlier than -90 crank angle degrees (°CA) after top dead center (aTDC), and transition from partial to full impingement between -65 and -90°CA aTDC. Based on this evidence, explanations for the combustion phasing advance at early injection timings are proposed along with potential verification experiments.
| Original language | English |
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| Title of host publication | Large Bore Engines; Fuels; Advanced Combustion |
| Publisher | American Society of Mechanical Engineers |
| ISBN (Electronic) | 9780791858318 |
| DOIs | |
| State | Published - 2017 |
| Event | ASME 2017 Internal Combustion Engine Division Fall Technical Conference, ICEF 2017 - Seattle, United States Duration: Oct 15 2017 → Oct 18 2017 |
Publication series
| Name | ASME 2017 Internal Combustion Engine Division Fall Technical Conference, ICEF 2017 |
|---|---|
| Volume | 1 |
Conference
| Conference | ASME 2017 Internal Combustion Engine Division Fall Technical Conference, ICEF 2017 |
|---|---|
| Country/Territory | United States |
| City | Seattle |
| Period | 10/15/17 → 10/18/17 |
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 nonexclusive, 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). 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. 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.