Experimental study of H2/air rotating detonation wave propagation characteristics at low injection pressure

• Published in: Aerospace science and technology Vol. 126; p. 107628
• Main Authors: Han, Jiaxiang, Bai, Qiaodong, Zhang, Shijian, Wu, Minxuan, Cui, Shengnan, Chen, Hao, Weng, Chunsheng
• Format: Journal Article
• Language: English
• Published: Elsevier Masson SAS 01.07.2022
• Subjects: Injection pressure; Longitudinal pulse detonation; Propagation mode; RDW velocity; Rotating detonation wave; Rotating detonation wave; RDW velocity; Injection pressure; Propagation mode; Longitudinal pulse detonation
• ISSN: 1270-9638; 1626-3219
• DOI: 10.1016/j.ast.2022.107628

H2/air rotating detonation wave (RDW) propagation characteristics were studied under low injection pressure. A small air mass flow rate and wide air injection ring were used to obtain low injection pressure. The formation of RDWs and the influence of different injection pressures on the RDW propagation process were studied and analyzed. The experimental results show that the lower limit of injection pressure for H2/air to form an RDW with stable propagation is 2.21 bar for hydrogen and 2.32 bar for air. At these injection pressures, the longitudinal pulsed detonation (LPD) mode and the single rotating detonation wave (SRDW) mode occur successively in the rotating detonation combustor (RDC), and the RDW velocity is 1491.4 m/s. The reasons for the generation, persistence and transformation of the LPD are analyzed. When the air mass flow rate is 370 g/s, the minimum air injection pressure to produce RDC ignition in a wide equivalence ratio range is 3.0 bar. With an equivalence ratio of 0.57–1.54, the RDW velocity and pressure first increase and then decrease, the maximum RDW velocity and pressure occur with an equivalence ratio of 1.2–1.3. RDW velocity and pressure increase with the air injection pressure rises. Flame characteristics during steady RDW propagation were analyzed using high-speed photography.