Effects of split injection strategies on evaporation dynamics and combustion performance: Role of first injection mass ratio in soot and NOx reduction

Weiwei Shang, Haizhao Li, Kang Yang, Haotian Qi and Keiya Nishida

Energy, 2025, vol. 332, issue C

Abstract: This study systematically investigates the effects of single and split diesel injection strategies on fuel-air mixing, evaporation, and combustion performance in a 2D piston cavity. Through laser absorption scattering (LAS) and two-color techniques, the injection rate, spray tip penetration, liquid/vapor-phase distribution, ignition timing (IT), and emissions characteristics were analyzed across four strategies: S160 (single injection) and D160_25:75, D160_50:50, D160_75:25 (split with 25 %, 50 %, and 75 % first-stage mass ratios, respectively). Results demonstrate that split injection significantly enhances fuel evaporation efficiency compared to single injection, while simultaneously reducing NOx and soot. The D160_75:25 strategy demonstrated optimal performance by achieving the highest vapor-phase homogeneity—as quantified through vapor-phase concentration distribution analysis (ranking: D160_75:25 > D160_25:75 > D160_50:50)—along with reduced wall-film formation and minimized NOx-soot trade-offs. Critical thresholds for ignition (vapor concentration >0.8 mg/cm3) and soot formation (>1 mg/cm3) were identified. The 75 % first-stage injection ratio emerged as the most balanced approach, improving combustion efficiency while aligning with tightening emission regulations. This work establishes a mechanistic framework for designing split injection systems that enhance energy conversion efficiency in diesel engines, offering a pragmatic pathway for decarbonizing non-electrified transport sectors.

Keywords: Split injection; Spray-wall interaction; Vapor-phase threshold; NOx-soot trade-off; Emission-intensity reduction (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544225028567
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:332:y:2025:i:c:s0360544225028567

DOI: 10.1016/j.energy.2025.137214

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 ().