RESEARCH PROGRESS ON FLASHBACK CHARACTERISTICS OF THE PREMIXED JET FLAMES OF HYDROGEN-RICH FUELS

Gas turbines are important power equipment and are significant for carbon neutrality. The use of hydrogen-rich fuel gas is an effective way to reduce its carbon emissions. The high chemical reactivity and fast combustion rate of hydrogen significantly increase the risk of flashback inside premixed combustion chambers, meaning the flame could potentially propagate back into the premixed gas supply pipeline. This paper reviews the representative experimental and numerical research progress on flashback in hydrogen-enriched fuel jet flames over the past 20 years. It introduces the research findings related to the influence of such as fuel hydrogen content, incoming flow temperature, working pressure, nozzle structure and size, thermoacoustic oscillations and micro-mixed burner on the flashback characteristics. Existing studies indicate that the main cause of flashback is the flame propagation speed exceeding the flow velocity in the boundary layer. Controlling the flow velocity and temperature, and modifying the local fuel concentration can overcome or retard the flashback. Based on the current research status and development trends, some prospective works are purposed.