Fundamental combustion properties of alternative fuels for energy transition

Sammanfattning: Validation and improvement of chemical kinetic modelling require accurate experimental data. The over goal of the present work is to obtain accurate data by using techniques that have been previously implemented in common flames, e.g. of methane, and showed good performance to provide high-value input for model validation of dimethyl ether (DME) combustion. Measurements of laminar burning velocity of premixed DME/air flames at standard pressure, elevated unburned gas mixture temperature 298-338 K, and at equivalence ratios Φ = 0.7-1.6 were performed by using the heat flux method that can create one-dimensional, non-stretched, adiabatic flames. In addition, the nitric oxide (NO) formation in the post-flame zone at the initial gas mixtures temperature of 338 K and atmospheric pressure was quantitatively studied by employing the calibrated saturated laser-induced fluorescence technique. The temperature dependence of the burning velocity was derived from the experimental results. The acquired data in terms of burning velocity and NO mole fraction were compared with literature data and predictions of six existing mechanisms. Simulation results from a model by Konnov et al. and the POLIMI CRECK mechanism agreed well with experimental data. The data can be considered as highly valuable input for continued model validation and development.