硅系延期体喷火火焰特性研究

Study on Output Flame Characteristics of Silicon Delay Element

为了探究延期体末端喷火段的火焰特性,采用硅系延期药制备了无切缝和有切缝两种延期体进行对比实验,通过高速相机和激光纹影测试系统观测延期体末端喷火火焰的流场结构,计算喷火火焰速度,以获得延期体喷火火焰特性与药芯燃烧传播稳定性的关系。结果表明:末端无切缝时,喷火火焰存在二次不稳定湍流火焰,其原因是由于内部气体积累而使药芯断裂,产生脉动燃烧现象;有切缝时,不存在二次湍流火焰,由于切缝的泄压作用,使药芯密度均匀,内部为稳定的层状燃烧。

In order to study the output flame characteristics of the delay element, two kinds of delay elements of slotting and non-slotting were prepared by the silicon delay composition, and the flow field structure of the flame was observed by the high-speed camera and laser schlieren test system, meanwhile, the flame output rate was calculated, to study the relationship between the flame characteristics of the delay element and the combustion stability of the core. The results show that the secondary unstable turbulent flame exists in the combustion of the output flame when the end is non-slotting, which is caused by internal gas accumulation leading to the core break and producing pulsating combustion. When there is a slotting, there is no secondary turbulent flame, which is due to the pressure relief of the slotting, and that could make the density of the core uniform and the internal laminar combustion stable.