Experimental investigation of pilot-fuel combustion in dual-fuel engines, Part 1: Thermodynamic analysis of combustion phenomena
Loading...
Author (Corporation)
Publication date
11.2019
Typ of student thesis
Course of study
Collections
Type
01A - Journal article
Editors
Editor (Corporation)
Supervisor
Parent work
Fuel
Special issue
DOI of the original publication
Link
Series
Series number
Volume
255
Issue / Number
Pages / Duration
115642
Patent number
Publisher / Publishing institution
Elsevier
Place of publication / Event location
Edition
Version
Programming language
Assignee
Practice partner / Client
Abstract
The pilot-fuel auto-ignition and combustion in compressed methane/air mixtures are investigated. Experiments were performed in an optically accessible rapid compression-expansion machine featuring quiescent charge conditions and a single-hole coaxial diesel injector mounted on the cylinder periphery. It enabled thermodynamic analysis of the pilot-fuel combustion without these phenomena being masked by the rapid premixed flame propagation like in the engine test rigs with turbulent charge. The aim of this study is to elucidate the first order influences of charge and pilot-fuel parameters on the ignition delay and transition into the premixed flame propagation. For this purpose, a comprehensive measurement matrix including variations of the premixed fuel equivalence ratio, charge temperature, and oxygen content as well as the variation of pilot injection duration is tested. The heat release rate (HRR) metrics describing the pilot-fuel combustion duration, peak HRR, and cumulative HRR during the pilot-fuel combustion are derived. Correlations of the HRR metrics to the ignition delay, pilot-fuel mixing state at ignition and the volume of the pilot-fuel jet are investigated. Methane is found to increase the ignition delay and prolong the pilot-fuel combustion duration. This effect is amplified for pilot injection strategies with leaner pilot-fuel mixtures at ignition or in the case of reduced charge oxygen content. Despite the reduced pilot-fuel reactivity the co-combustion of entrained methane leads to higher peak-HRR, except in the reduced charge oxygen cases, where the excessively reduced mixture reactivity with the introduction of methane leads even to a reduced peak-HRR. The phenomenology of the dual-fuel combustion process is described in Part 1, whereas Part 2 of this work aims at improving the understanding of the underlying processes by application of advanced optical diagnostic methods.
Keywords
Event
Exhibition start date
Exhibition end date
Conference start date
Conference end date
Date of the last check
ISBN
ISSN
0016-2361
1873-7153
1873-7153
Language
English
Created during FHNW affiliation
Yes
Strategic action fields FHNW
Publication status
Published
Review
Peer review of the complete publication
Open access category
Closed
License
Citation
Srna, A., von Rotz, B., Herrmann, K., Boulouchos, K., & Bruneaux, G. (2019). Experimental investigation of pilot-fuel combustion in dual-fuel engines, Part 1: Thermodynamic analysis of combustion phenomena. Fuel, 255, 115642. https://doi.org/10.1016/j.fuel.2019.115642