Laminar Burning Speed Measurements of Dimethyl Ether–Hydrocarbon Mixtures

Abstract

Abstract. Fossil fuels, when burned in the air, release large amounts of carbon dioxide (CO2) and greenhouse gases into the air, causing significant pollution. To reduce greenhouse gas emissions (CO2, CO, and NOx), alternative fuels such as dimethyl ether (DME) are being explored for their potential to offer cleaner combustion solutions. This study investigates the laminar burning speed (LBS) DME blends with several alkanes and alkenes in air at atmospheric pressure (1 atm) across a wide range of equivalence ratios (ϕ). LBS is essential for understanding combustion characteristics, including combustion efficiency, heat release rates, and chemical kinetics. Accurate LBS measurements are vital in optimizing combustion system designs, such as those used in gas turbines and internal combustion engines, where efficient fuel burn and minimal pollutant formation are critical. To comprehend the performance and usability of these fuels in gas turbines, measurements of parameters like ignition delay time and LBS are required. DME–propane mixtures are exciting in this study due to their potential for enhanced combustion stability and flame propagation. Here, we report data on observations of these fuels' laminar burning speed up to an initial pressure of 1 atm and an initial temperature of 295 K. The LBS measurements were performed using a spherical chamber with Schlieren imaging techniques to visualize the flame front and ensure precise tracking of flame propagation. The unburned gas was maintained at ambient temperature, with precautions to minimize heat loss. Results indicate that LBS varies significantly with the equivalence ratio, reaching its maximum near stoichiometric conditions for all fuels. As part of the validation procedure for the results, they are also contrasted with the performance of comprehensive kinetic models.