壁温蒸发器对脉冲爆震发动机工作性能的影响

设计了脉冲爆震发动机(PDE)壁温蒸发器,利用PDE工作时的壁温对煤油进行预蒸发,以改善煤油在PDE中的起爆性能。通过适当设计的油路系统将煤油蒸汽供入由汽油启动工作的PDE中,在改变PDE工作频率、蒸发器供气量和PDE煤油/汽油比例等条件下,对PDE的爆震特性进行了研究。研究结果表明,不同工作频率和蒸发器内的余气系数对PDE点火、起爆特性和爆震波压力、速度特性均有明显影响。使用经过预蒸发的煤油/汽油混合燃料能有效缩短点火时间和爆震波形成过程,对煤油进行预蒸发可以很好地提高多循环、吸气式两相PDE的爆震特性。

Effect of Wall-evaporator on Performance of a Pulse Detonation Engine

With an annular evaporator wrapped outside the detonation tube of a pulse detonation engine (PDE), kerosene is heated by the high wall temperature of tube prior to being fed into the PDE, which has already been initiated by gasoline. With well designed intake valve the kerosene steam is fed into the PDE after it has started working steadily. Research work is carried out on evaporator-PDE characteristics under different frequencies, evaporator air fluxes and ratios of kerosene to gasoline in the PDE. It shows that PDE operation frequency and air-fuel equivalence ratio in the evaporator play a distinct role in the process of detonation ignition and initiation as well as the characteristics of detonation wave pressure and velocity. Using the kerosene steam, the time needed to initiate detonation wave can be considerably reduced. It proves that pre-evaporated kerosene heated by the wall temperature of a multi-cycle air breathing PDE may significantly improve PDE performance.