Study on the Effects of Inflow Parameters on the Auto-Initiation of Hydrogen-Rich Gas Rotating Detonation

To obtain a comprehensive understanding of the auto-initiation characteristics of rotating detonation with the high-temperature hydrogen-rich gas. The experiment was carried out with hydrogen-rich gas as fuel and ambient temperature air as oxidant. The high-temperature hydrogen-rich gas was a kind of fuel-rich gas produced by the pre-combustion of hydrogen and oxygen. The effects of inflow parameters such as air mass flow rate, hydrogen mass flow rate, and hydrogen-rich gas temperature on the auto-initiation delay time and velocity of rotating detonation waves (RDWs) were experimentally studied. The experimental results showed that when the hydrogen and air mass flow rates were 6.3 ~ 17.4 g/s and 314 ~ 610 g/s, respectively, auto-initiation could be successfully achieved and a stable RDW could be formed. As the hydrogen and air mass flow rates increased, the auto-initiation delay times decreased from 40 to 5 ms and from 45 to 19 ms, respectively. When the temperature of the hydrogen-rich gas increased from 460 to 690 K, the auto-initiation delay time decreased from 100 to 10 ms, the RDW velocity decreased from 1368.5 to 1231 m/s. Hydrogen-rich gas has a high temperature, which is easy to cause the non-detonative combustion ahead of the wave of air and hydrogen-rich gas in the RDC, which consumes part of the fuel and resulting in a decrease in the RDW velocity.