Laminar burning velocities of high-performance fuels relevant to the Co-Optima initiative 2019-01-0571
Co-Optimization of Fuels and Engines initiative of the U.S Department of Energy initiated investigations on several candidates of biofuels and blends for internal combustion engines. Several biofuels were selected by screening criteria, which were boiling point, toxicity, research octane number, octane sensitivity, laminar flame speed, and economical distribution system, etc. In this study, we focused our investigation on three of the fuels candidates; ethanol, 2-methylfuran, and methyl acetate. While there exist many studies for ethanol, there are only few studies on combustion characteristics of 2-methylfuran and methyl acetate in the literature. Measurements of properties such as ignition delay time and laminar burning velocity (LBV) are necessary for these fuels in order to understand their performance and applicability in engines. We present measurements of laminar burning velocities of these fuels at an initial pressure of 1 atm and initial temperature of 428 K. Equivalence ratio was varied in a wide range to examine the effects on laminar burning velocity for each fuel. Laminar burning velocity of methyl acetate was slower than the other fuels, showing the lowest values for all equivalence ratios. Ethanol and 2-methlyfuran appear to have similar laminar burning velocities, but the values of 2-methylfuran were slightly higher than those of ethanol at high equivalence ratio. The results presented are also compared with the performance of detailed kinetic models as part of their validation process. The kinetic model is used to explore the source of the differences in the observed laminar burning velocities of the fuels.
Gihun Kim, Bader Almansour, Suhyeon Park, Anthony Terracciano, Subith Vasu, Kuiwen Zhang, Scott Wagnon, William Pitz
University Of Central Florida, Public Authority for Applied Education and Training, University of Central Florida, LLNL, Lawrence Livermore National Lab