Optimization of ethanol injected ratio of a stoichiometric spark-ignited ethanol port-injected plus gasoline direct-injected engine at various throttle openings

Changming Gong, Wei Huang and Fenghua Liu

Energy, 2025, vol. 316, issue C

Abstract: Ethanol can effectively reduce particulate emissions of engine owing to the high octane value and oxygen level. The impacts of ratio of ethanol port-injected (REPI) on combustion and emissions of a stoichiometric spark-ignited ethanol port-injected (EPI) plus gasoline direct-injected (GDI) engine at various throttle openings (TO) were investigated by experiment. Results show that the best combustion performances can be obtain at REPI = 35 % and 30 % for TO = 7 % and 10 %, separately. The COVimep (coefficient of variation of indicated mean effective pressure) can be limited within 1.3 % in all operating condition. The REPI had a little impact on COVimep under various TOs. At TO = 7 %, CO and HC emissions decreased with the increase of REPI. At TO = 10 %, CO and HC emissions achieved the lowest at REPI = 40 % and 30 % separately. NOX formation depended on the oxygen concentration and charge cooling effect. NOX emissions achieved the lowest at REPI = 30 % and 35 % for TO = 7 % and 10 % separately. At REPI<30 %, NOX TO = 10 %≫NOX TO = 7 %; at REPI>35 %, NOX TO = 10 %>NOX TO = 7 %. The soot emission decreased with increasing REPI; at a constant REPI, sootTO = 10 %>sootTO = 7 %. By compromising combustion and emissions performances, when TO was 7 % and 10 %, the ideal REPI was 35 % and 30 %, separately. Increasing TO would decrease the ideal REPI.

Keywords: Spark-ignited engine; Ethanol port-injected plus gasoline direct-injected; Ratio of ethanol port-injected; Stoichiometric mixture (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544225002154
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:316:y:2025:i:c:s0360544225002154

DOI: 10.1016/j.energy.2025.134573

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().