| Autor: |
Ibron, Christian, Fatehi, Hesammedin, Wang, Zhenkan, Stamatoglou, Panagiota, Lundgren, Marcus, Aldén, Marcus, Richter, Mattias, Andersson, Öivind, Bai, Xue-Song |
| Zdroj: |
Proceedings of the Combustion Institute; 2020, Vol. 38 Issue 4, p5703-5711, 9p |
| Abstrakt: |
The ignition process, mode of combustion and reaction front propagation in a partially premixed combustion (PPC) engine running with a primary reference fuel (87% iso-octane, 13% n-heptane by volume) is studied numerically in a large eddy simulation. Different combustion modes, ignition front propagation, premixed flame and non-premixed flame, are observed simultaneously. Displacement speed of CO iso-surface propagation describes the transition of premixed auto-ignition to non-premixed flame. High temporal resolution optical data of CH 2 O and chemiluminescence are compared with simulated results. A high speed ignition front is seen to expand through fuel-rich mixture and stabilize around stoichiometry in a non-premixed flame while lean premixed combustion occurs in the spray wake at a much slower pace. A good qualitative agreement of the distribution of chemiluminescence and CH 2 O formation and destruction shows that the simulation approach sufficiently captures the driving physics of mixed-mode combustion in PPC engines. The study shows that the transition from auto-ignition to flame occurs over a period of several crank angles and the reaction front propagation can be captured using the described model. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
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