Shock Tube and Flame Speed Measurements of 2,4,4-Trimethyl-1-Pentene: A Co-Optima Biofuel

Abstract

The combustion of 2,4,4-trimethyl-1-pentene (diisobutylene, C8H16), which is a biofuel and a component of surrogate fuels, is examined in this work. Carbon monoxide time-histories and ignition delay times are collected behind reflected shock waves utilizing a shock tube and mid-infrared laser absorption spectroscopy. Measurements were obtained near 10 atm pressure during stoichiometric oxidation of 0.15%C8H16/O2/Ar. Simulated results from chemical kinetic models are provided, and sensitivity analyses are used to discuss differences between models for both ignition delay times and carbon monoxide formation. In addition, laminar burning speeds are obtained at 1 atm, 428 K, and equivalence ratios, phi, between 0.91-1.52 inside a spherical chamber facility. Measured burning speeds are found to be less than that of ethanol over the equivalence ratio span. Flame speed measurements are compared to predictions of chemical kinetic mechanisms and are in agreement for the richest conditions; however, at lean conditions, the model predicts a far slower-burning speed. The maximum burning speed occurs at an equivalence ratio of 1.08 with a magnitude of 0.70 m/s. Current work provides the crucial experimental data needed for assessing the feasibility of this biofuel and for the development of future combustion chemical kinetics models.

A comprehensive experimental and kinetic modeling study of di-isobutylene isomers: Part 1

“…The LBV of DIB-1/air flames obtained by Laich et al [21] at 428 K better agree with the trendlines in Figs. 18 and 19 , though some datapoints, e.g., for ϕ = 0.9 and 1.4 are obvious outliers.…”

“…18 and 19 , though some datapoints, e.g., for ϕ = 0.9 and 1.4 are obvious outliers. It should be noted that the measurements [21] were performed at higher than other datasets in Fig. 20 , though within overlapping error bars reflecting lower than expected LBV values at 400 K as seen in Figs.…”

“…Laich et al implemented a multi-zone model to derive LBVs from pressure traces and thus ignored stretch correction. These measurements [21] were compared with the results of Zheng et al at 1 atm and appeared to be slightly higher (for fuel-lean mixtures) or lower (for fuel-rich mixtures) compared to the LBVs measured by Zheng et al at 450 K [13] .…”

“…Most recently the burning velocities of DIB-1 were determined in spherical flames at 1 atm and at an initial temperature of 428 K [21] . Laich et al implemented a multi-zone model to derive LBVs from pressure traces and thus ignored stretch correction.…”