Abstract
A wide variety of high temperature experimental data obtained in this study complement the data on the oxidation of the two di-isobutylene isomers presented in Part I and offers a basis for an extensive validation of the kinetic model developed in this study. Due to the increasing importance of unimolecular decomposition reactions in high-temperature combustion, we have investigated the di-isobutylene isomers in high dilution utilizing a pyrolysis microflow reactor and detected radical intermediates and stable products using vacuum ultraviolet (VUV) synchrotron radiation and photoelectron photoion coincidence (PEPICO) spectroscopy. Additional speciation data at oxidative conditions were also recorded utilizing a plug flow reactor at atmospheric pressure in the temperature range 725–1150 K at equivalence ratios of 1.0 and 3.0 and at residence times of 0.35 s and 0.22 s, respectively. Combustion products were analyzed using gas chromatography (GC) and mass spectrometry (MS). Ignition delay time measurements for di-isobutylene were performed at pressures of 15 and 30 bar at equivalence ratios of 0.5, 1.0, and 2.0 diluted in ‘air’ in the temperature range 900–1400 K using a high-pressure shock-tube facility. New measurements of the laminar burning velocities of di-isobutylene/air flames are also presented. The experiments were performed using the heat flux method at atmospheric pressure and initial temperatures of 298–358 K. Moreover, data consistency was assessed with the help of analysis of the temperature and pressure dependencies of laminar burning velocity measurements, which was interpreted using an empirical power-law expression. Electronic structure calculations were performed to compute the energy barriers to the formation of many of the product species formed. The predictions of the present mechanism were found to be in adequate agreement with the wide variety of experimental measurements performed.
| Original language | English |
|---|---|
| Article number | 112547 |
| Journal | Combustion and Flame |
| Volume | 251 |
| DOIs | |
| State | Published - May 2023 |
| Externally published | Yes |
Funding
This work was supported by the Knut and Alice Wallenberg Foundation through grant KAW2019.0084 COCALD, Sweden. The study was also supported by the grant from the Russian Science Foundation (project No. 22-779-10205). M.S. A.B and P.H acknowledge funding by the Swiss Federal Office of Energy (SI/501269-01). The pyrolysis measurements were carried out at the VUV beamline of the Swiss Light Source, located at Paul Scherrer Institute in Villigen (Switzerland). The work at LLNL was performed under the auspices of the U.S. Department of Energy (DOE) by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and was conducted as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the DOE Office of Energy Efficiency and Renewable Energy (EERE). Work at the National Renewable Energy Laboratory was performed under Contract No. DE347AC36-99GO10337 as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy Bioenergy Technologies Office and Vehicle Technologies Office. The authors at NUI Galway recognize funding support from Science Foundation Ireland (SFI) via project numbers 15/IA/3177 and 16/SP/3829. The authors at CNRS Orléans recognize funding support from the Agence Nationale de la Recherche (ANR) via the Labex CAPRYSSES (ANR- 11-LABX-006-01). This work was supported by the Knut and Alice Wallenberg Foundation through grant KAW2019.0084 COCALD, Sweden. The study was also supported by the grant from the Russian Science Foundation (project No. 22-779-10205). M.S., A.B and P.H acknowledge funding by the Swiss Federal Office of Energy (SI/501269-01). The pyrolysis measurements were carried out at the VUV beamline of the Swiss Light Source, located at Paul Scherrer Institute in Villigen (Switzerland). The work at LLNL was performed under the auspices of the U.S. Department of Energy (DOE) by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and was conducted as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the DOE Office of Energy Efficiency and Renewable Energy (EERE). Work at the National Renewable Energy Laboratory was performed under Contract No. DE347AC36-99GO10337 as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy Bioenergy Technologies Office and Vehicle Technologies Office. The authors at NUI Galway recognize funding support from Science Foundation Ireland (SFI) via project numbers 15/IA/3177 and 16/SP/3829. The authors at CNRS Orléans recognize funding support from the Agence Nationale de la Recherche (ANR) via the Labex CAPRYSSES (ANR- 11-LABX-006-01).
Keywords
- Burning velocity
- Di-isobutylene
- Kinetic modeling
- Pyrolysis, ignition delay