燃烧室宽度对煤油旋转爆震波传播模态的影响

To investigate the propagation characteristics of rotating detonation waves utilizing liquid kerosene, this experimental study has been performed in a laboratory-scale rotating detonation combustor. Kerosene and oxygen-enriched air with an oxygen volume fraction of 40% have been used as fuel and oxidizer respectively. One hollow combustor and annular combustors with combustor widths of 32mm, 26mm and 20mm, respectively, have been considered based on a fixed outer diameter of 100mm. Four propagating modes, i.e., the fast deflagration mode, the quasi-stable detonation mode, the dual-wave collision mode, and the stable rotating detonation mode, have been observed at different oxidizer mass flow rates and their propagation characteristics have been discussed. In the hollow combustor, stable detonation waves cannot propagate and the fast deflagration mode and the quasi-stable detonation mode are able to be observed with smaller oxidizer mass flow rates. As the oxidizer mass flow rate is larger than 154g/s, the stable detonation mode is easily to be obtained, which average propagation velocities and peak pressures of rotating detonation waves are around 1750m/s and 0.7MPa, respectively. In the annular combustor, the average propagation velocities of rotating detonation waves are around 1245~1465m/s, which are obviously lower than the values in the hollow combustor. Besides, the range of the stable detonation mode is narrowed and the average propagation velocity is decreased when the combustor width is reduced. As a result, the combustor with a larger width is a more favorable choice to obtain stable rotating detonation waves utilizing liquid kerosene in the present study.