固冲发动机连管进气道弯头改进设计
2014-09-02张义飞王希亮贺永杰
张义飞+王希亮+贺永杰
【摘 要】本文针对某固冲发动机连管试验时出现的保护套烧蚀现象,分析了造成烧蚀的原因,提出了改进方案;采用数值模拟的方法对不同的整流板布局方案进行了优选,确定了最终的改进措施,并进行了试验验证;试验结果表明:在连管试验进气道弯头内增加直板形整流板可以有效的解决保护套烧蚀问题,该方案可为其他冲压发动机解决类似问题提供参考。
【关键词】固冲发动机;连管进气道;改进设计;整流板
Improvement Design for Elbow of Connected-pipe Inlet of Solid Ducted Rocket
ZHANG Yi-fei WANG Xi-liang HE Yong-jie
(China Airborne Missile Academy, Luoyang Henan 471009, China)
【Abstract】The reason of ablation of protecting jacket for inlet port on connected-pipe experiment is analyzed and improvement design was presented. Different layout of diversion plate has been investigated by numerical simulation and the optimal configuration of diversion plate has been obtained. The result of experiment showed that adding a flat diversion plate in the elbow of connected-pipe inlet could resolve effectively the question of protecting jacket ablation and this scheme could been used as a reference for other solid ducted rocket which has similar question.
【Key words】Solid ducted rocket; Connected-pipe inlet; Improvement design; Diversion plate
对于采用旁侧进气道的固冲发动机来说,气流必须经过转弯段才能进入补燃室与一次燃气进行掺混燃烧。进气道转弯的角度和结构一般根据发动机性能要求和总体结构布局确定[1-3]。由于受气动外形的限制,弯头段的转弯半径要求尽量小,以便减小阻力,但小的转弯半径有可能给进气道内的气体流动造成不利影响。比如在进气道弯头转弯内角处产生较大的气流分离,使进气道出口截面的流场畸变指数增加。另外在气流分离处由于压强相对较高,补燃室的高温燃气会向弯头内回流,造成此处温度过高,在长时间工作过程中有可能被烧穿,导致试验失败。在某试验型固体火箭冲压发动机的地面连管试验中,就曾多次发现进气道出口处的保护套有被烧蚀的痕迹。因此需要采取措施对进气道及弯头处进行改进设计。
1 原因分析及改进方案
图1为原进气道及弯头的结构示意图。经分析,造成弯头处气流分离的原因主要有:(1)弯头转弯段内侧转弯半径过小;……
