某型蒸发式稳定器气动及燃烧特性研究

为解决亚燃冲压发动机在高速低温来流条件下的可靠点火、火焰稳定和高效燃烧问题,对某型蒸发式火焰稳定器分别进行了冷态流场和燃烧流场的数值研究,并与常规V型火焰稳定器进行了对比分析。研究结果表明:在给定范围内,蒸发式稳定器随来流速度的增大,总压恢复系数和停留时间明显减小,回流区长度、回流率和燃烧效率变化不大;与相同槽宽的常规V型火焰稳定器相比,回流率明显减小,总压恢复系数、回流区长度和停留时间略有减小。蒸发式稳定器后部形成明显的回流区,且基本上不受外部主流流动的干扰,通过单独控制稳定器局部供油,可以使稳定器在最佳油气比下工作,有利于在高速来流条件下可靠工作。

Investigation on aerodynamic and combustion characteristics of an evaporating flame-holder

To realize reliable ignition,flame stabilization and effective combustion of a ramjet engine under the condition of low-temperature and high-velocity incoming flow,numerical analysis of cold-state and combustion flow fields for an evaporating flame-holder was completed,and contrastive analysis with the V-gutter flame-holder was performed.The results show that,in a given scope,with the increase of inlet velocity,the total pressure recovery coefficient and retention time are reduced obviously,and recirculation zone length,recirculation ratio and combustion efficiency change a little.Compared to the V-gutter flame-holder,the recirculation ratio is reduced more significantly,and the total pressure recovery coefficient,recirculation zone length,and retention time are decreased a little bit.Recirculation zone happens in downriver of evaporating flame-holder,and is not interfered by main-flow.The flame-holder can work at the best fuel-air mass ratio by local fuel supply and adapt to low-temperature high-velocity inlet environment.