Developing a Detailed Chemical Kinetic Model for Combustion of Iso-Cetane Based on Ignition and Oxidation
Pan Chen1, Yijun Heng2, Bohui Zhao1
1School of Naval Architecture, Ocean and Energy Power Engineering, Wuhan University of Technology, Wuhan 430063, China.
Molecules (Basel, Switzerland)
|May 13, 2026
Summary
This study improves the chemical kinetic model for iso-cetane, a key component in diesel surrogate fuels. The enhanced model accurately predicts ignition delay times and reveals the mechanisms behind the negative temperature coefficient (NTC) region.
Area of Science:
- Combustion Chemistry
- Chemical Kinetics
- Surrogate Fuels
Background:
- Iso-cetane is crucial for modeling diesel surrogate fuels, but existing kinetic models lack predictive accuracy.
- Accurate chemical kinetic models are essential for understanding and optimizing combustion processes.
Purpose of the Study:
- To develop an improved detailed chemical kinetic model for iso-cetane.
- To enhance the predictive accuracy of iso-cetane combustion, particularly its ignition delay time (IDT).
- To elucidate the reaction pathways contributing to the negative temperature coefficient (NTC) phenomenon in iso-cetane ignition.
Main Methods:
- Updated thermodynamic data for iso-cetane and its intermediates.
- Systematic analysis of reaction effects on IDT and targeted modifications of rate constants.
- Development of a comprehensive kinetic model with 4541 species and 18,359 reactions.
- Validation against experimental data for IDT and species concentrations.
- Sensitivity and reaction pathway analyses to understand ignition mechanisms.
Main Results:
- A new detailed chemical kinetic model for iso-cetane was developed and validated.
- The improved model demonstrates enhanced predictive performance for ignition delay times.
- Key reaction pathways influencing iso-cetane oxidation and NTC behavior were identified.
Conclusions:
- The developed kinetic model provides a more accurate representation of iso-cetane combustion.
- The study clarifies the intrinsic link between competing chain-branching and chain-propagating pathways and the NTC region.
- This work contributes to the fundamental understanding of branched-chain alkane combustion for diesel applications.
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