A skeletal mechanism for gasoline flame ionization process prediction on HCCI engines was developed based on a primary reference fuel oxidation mechanism and a C1-C4 hydrocarbon flame ionization mechanism. Since the ion concentrations significantly affect the aroused ion current signals the mechanism is targeted on accurately predicting both the ion production concentrations and other key combustion characteristics. Comparison between the detailed gasoline flame ionization mechanism and experimental results revealed that the predicted maximum hydronium ion concentration and the concentration variation tendency are validated. Also the auto-ignition delay time accurately predicted under HCCI engine conditions. Through coupling with a three-dimensional CFD engine model the skeletal mechanism was applied to predict the important information of in-cylinder ion species. The results show that the ion current phase matched well with the positions where the predicted ion concentration reached its maximum and the ion current amplitudes were well predicted under varying conditions of various equivalence ratios and fuel injection ratios.
Bibliographical noteFunding Information:
This research was supported by the National Science Foundation of China (No. 51376139), the Specialised Research Fund for the Doctoral Program of Higher Education of China (No. 20120072110015) and the fund of Committee Shanghai Science and Technology (11DZ2260400).
- Combustion phase
- Flame ionization
- Ion current
- Skeletal mechanism
ASJC Scopus subject areas
- General Chemical Engineering
- Mechanical Engineering
- Physical and Theoretical Chemistry