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Summary Premixed flames play a prominent role in combustion systems such as aircraft combustors, gas turbines and internal combustion engines. Current fuels are also derived from fossil sources, including coal, petrol, gasoline, natural gas or liquefied petroleum gas. Alternatively, liquid and gaseous biofuels, such as ethanol and biodiesel, hydrogen, wood gas or coal gas, can be used with appropriate modifications. Furthermore, the components of oxygenated fuel are known for their reduction of soot particles in diesel combustion processes while having little effect on nitrogen oxide (NOX) emissions. The advantage of C1‐oxygenate dimethoxymethane (OME1, also called “methylal” or DMM) is the lack of CC bonds in their molecular structure. OME1 belongs to the group of oxymethylene ethers (OMEn) with the molecular structure CH3O(CH2O)nCH3 where n = 1 (short molecular structure: C3H8O2). This experimental and numerical study aims to investigate the laminar burning velocity (LBV) of the oxymethylene ether (OMEn, n = 1), the influence of temperature and nitrogen dilution. To our knowledge, no studies have been conducted with regards to nitrogen dilution during the measurements of OME1 burning velocity. In this study, a heat‐flux burner setup was used to investigate the LBV for equivalence ratios from 0.7 to 1.6. The experimental LBV data shows a decreasing nonlinear influence of nitrogen dilution effects for 0% to 70% and increasing linear with preheating up to 373 K. The numerical results were compared with the experiments conducted with simple alcohols (ethanol) and C3 hydrocarbon fuels (propane). Existing numerical reaction mechanisms can only partially reproduce the new experimental data. Finally, a sensitivity analysis was conducted by changing various parameters during the numerical investigations, in order to clarify the discrepancy.

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Rapid compression machine, shock-tube, plug-flow reactor, and heat-flux burner experiments were performed for stoichiometric and fuel-rich ethanol/air mixtures. The experimental ignition delay time conditions included temperatures from 801 to 1313 K at pressures of approximately 10, 20, and 40 bar. Species concentration profiles are measured in a range from 423 to 973 K at a pressure of 6 bar, and laminar burning velocities are measured in a range of 358–388 K at a pressure of 1 bar. The experimental results were simulated using the detailed reaction mechanism AramcoMech 3.0, showing that this mechanism is well suited even for the large range of experimental conditions covered in our work. Furthermore, a reduced mechanism was developed and validated with our experimental data. The sarting point for the reduced mechanism is an already existing reduced reaction mechanism (UCB Chen) for methane, ethane, and propane oxidations. Additional reactions for the ethanol subsystem were taken from AramcoMech 3.0. They were chosen according to their importance in representing the experimental data in simulations with the detailed AramcoMech 3.0, resulting in four additional species and 27 additional reactions. The performance of the reduced mechanism was compared against experimental results from this work, from the literature, and against simulations based on the detailed reaction mechanism. The reduced mechanism shows only minor differences in the results compared to the detailed AramcoMech 3.0. It reproduces very well experimentally with determined ignition delay times of ethanol/argon/nitrogen/oxygen mixtures with inert gas/oxygen ratios between 3.76 and 7.52 (molar), equivalence ratios between 1 and 2 in a temperature range from 848 to 1313 K, and pressures from 10 to 40 bar. Furthermore, it can also predict with a high accuracy laminar burning velocities and species profiles in plug-flow reactors.