Large-eddy simulation of dual-fuel spray ignition at different ambient temperatures

Bulut Tekgül*, Heikki Kahila, Ossi Kaario, Ville Vuorinen

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

29 Downloads (Pure)

Abstract

Here, a finite-rate chemistry large-eddy simulation (LES) solver is utilized to investigate dual-fuel (DF) ignition process of n-dodecane spray injection into a methane–air mixture at engine-relevant ambient temperatures. The investigated configurations correspond to single-fuel (SF) ϕCH4= 0 and DF ϕCH4= 0.5 conditions for a range of temperatures. The simulation setup is a continuation of the work by Kahila et al. (2019, Combustion and Flame) with the baseline SF spray setup corresponding to the Engine Combustion Network (ECN) Spray A configuration. First, ignition is investigated at different ambient temperatures in 0D and 1D studies in order to isolate the effect of chemistry and chemical mechanism selection to ignition delay time (IDT). Second, 3D LES of SF and DF sprays at three different ambient temperatures is carried out. Third, a reaction sensitivity analysis is performed to investigate the effect of ambient temperature on the most sensitive reactions. The main findings of the paper are as follows: (1) DF ignition characteristics depend on the choice of chemical mechanism, particularly at lower temperatures. (2) Addition of methane to the ambient mixture delays ignition, and this effect is the strongest at lower temperatures. (3) While the inhibiting effect of methane on low- and high-temperature IDT's is evident, the time difference between these two stages is shown to be only slightly dependent on temperature. (4) Reaction sensitivity analysis indicates that reactions related to methane oxidation are more pronounced at lower temperatures. The provided quantitative results indicate the strong ambient temperature sensitivity of the DF ignition process.

Original languageEnglish
Pages (from-to)51-65
Number of pages15
JournalCombustion and Flame
Volume215
DOIs
Publication statusPublished - 1 May 2020
MoE publication typeA1 Journal article-refereed

Keywords

  • Ambient temperature
  • Dual-fuel
  • ECN Spray A
  • IDT
  • Ignition
  • Large-eddy simulation

Fingerprint Dive into the research topics of 'Large-eddy simulation of dual-fuel spray ignition at different ambient temperatures'. Together they form a unique fingerprint.

  • Projects

    Tri-Reactivity Ignition: Simulation and Experiments

    Vuorinen, V., Gadalla, M., Kannan, J. & Cheng, Q.

    01/09/201830/09/2022

    Project: Academy of Finland: Other research funding

    Clean and Efficient Gas Combustion: Numerical Simulation of Simultaneous Combustion of Two Fuels

    Kaario, O., Tekgül, B., Keskinen, K., Ahmad, Z., Ranta, O., Ainsalo, A. & Gadalla, M.

    01/09/201530/09/2019

    Project: Academy of Finland: Other research funding

    Equipment

    Science-IT

    Mikko Hakala (Manager)

    School of Science

    Facility/equipment: Facility

  • Cite this