固体燃料冲压发动机旋流燃烧特性试验

为研究固体燃料冲压发动机旋流燃烧特性,进行了直流与旋流对比直连式试验。固体装药内径40mm,长180 mm,成分为HTPB中加入65%的金属粉末。试验发动机采用火炬式点火器点火,空气由燃烧补氧式空气加热器加热至690 K,热空气流量300 g/s。试验测量了压力、推力等参数,使用监控录像对发动机尾焰进行拍摄,通过测量试验前后装药质量差获得固体燃料平均燃速。旋流试验未将旋流器伸入燃烧室即实现了火焰稳定,且旋流燃烧比直流燃烧表现出更好的稳定性,平均燃速较直流提高近50%。旋流燃烧尾焰存在明显的径向扩张,表明尾焰仍有切向动量,损失了部分推力。

Experiment on swirl combustion characteristics of solid fuel ramjet

In order to study the swirl combustion characteristics of solid fuel ramjet,direct/swirl flow contrast experiments were conducted on a direct-connected pipe test bed.The solid fuel contained 65% metal powder based on HTPB.The initial port diameter of the solid fuel was 40 mm,and the length was 180 mm.An ethanol/oxygen spark torch igniter was used for the ignition of solid fuel.Inlet air was heated up to 690 K,and oxygen was mixed with air to ensure that the vitiated air contained 23% oxygen.The flux of the vitiated hot air was about 300 g/s.The pressure and thrust were measured.A video was used to record the tail flame,and the mean solid fuel regression rate was calculated.The flam was stable without inserting the swirler into the combustion chamber.The swirl flow combustion performed better stabilization than the direct flow,and the mean solid fuel regression rate was nearly 50% higher than the direct flow.The tail flame expanded in the radial direction.This indicated that the combustion products still existed tangential velocity,which caused thrust loss.