关键词: 硼粉, 混合爆轰, 临界起爆能量, 粉末爆轰发动机

Abstract: Boron powder, due to its high calorific value and excellent density-specific impulse characteristics, demonstrates significant application value in the field of detonation engines. To investigate the critical initiation energy of boron/ethylene/oxygen hybrid detonation, a self-built constant-volume combustion chamber (hereinafter referred to as the detonation chamber) was employed, utilizing a pre-detonation tube for ignition initiation. By varying the boron equivalence ratio, initial total pressure, and the equivalence ratio partitioning between boron and ethylene within the chamber, the influence mechanisms of these factors on the critical initiation energy were revealed.Experimental results show that under the initial pressure of 48 kPa and ethylene/oxygen equivalence ratio of 0.6 , as the boron equivalence ratio increases, the critical initiation energy of hybrid detonation increases firstly and then decreases. At a global equivalence ratio of 1.6, the critical initiation energy decreases with increasing initial pressure. Notably, when the initial pressure is increased to 72 kPa and 96 kPa, low-velocity detonation phenomena occur below the direct initiation energy threshold. At the initial pressure of 48 kPa initial pressure and global equivalence ratio of 1.0 , lower ethylene proportion leads to a higher critical initiation energy. When the ethylene equivalence ratio decreases to 0.4, hybrid detonation becomes difficult to be initiated.Through studying the variation patterns of critical initiation energy for boron/ethylene/oxygen hybrid detonation under different conditions, this research provides theoretical foundations for the initiation of boron powder detonation engines.

Key words: boron powder, hybrid detonation, critical initiation energy, powder detonation engine