Kinetic Study of Methyl Palmitate Oxidation in a Jet-Stirred Reactor and an Opposed-Flow Diffusion Flame Using a Semidetailed Mechanism

Abstract

Methyl palmitate is a long-chain methyl ester and a major constituent of palm-oil-derived biodiesel. A detailed mechanism for its combustion was recently developed by Herbinet and coworkers. This detailed mechanism involves 4442 species and 30,425 reactions, which makes it too complex for direct use in flame structure modeling, for instance, in studies of one-dimensional laminar opposed-flow diffusion flames. We used the improved directed relation graph method to derive a skeletal biodiesel combustion mechanism that retains the key properties of the detailed mechanism including auto-ignition behaviors and extinction temperature profiles of stoichiometric methyl palmitate/air mixture at pressures of 1–100 atm. The initial temperatures for ignition were from 600 to 1600 K. This skeletal mechanism, containing only 402 species and 2503 reactions, was used to study methyl palmitate conversion rates and key species profiles in a jet-stirred reactor and an opposed-flow diffusion flame at atmospheric pressure and stoichiometric fuel/oxidizer conditions.

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Keywords:

• Diffusion flame
• Jet-stirred reactor
• Methyl palmitate
• Oxidation
• Skeletal mechanism

ACKNOWLEDGMENTS

This project was partially funded through Engine Research Center (CERC) at Chalmers University of Technology. The work at UConn was supported by the National Science Foundation under Grant 0904771. The authors gratefully acknowledge Olivier Herbinet from CNRS, Nancy University in France, for sharing the EXGAS software package and the detailed combustion mechanism for methyl palmitate.