### 喷注流强分布对高频纵向燃烧不稳定抑制效果研究

1. 1. 西安航天动力研究所
2.
3. 航天工程大学
4. 西安航天动力研究所 液体火箭发动机技术重点实验室
• 收稿日期:2021-06-25 修回日期:2021-09-27 出版日期:2021-10-09 发布日期:2021-10-09
• 通讯作者: 汪广旭
• 基金资助:
装备预研重点实验室基金

### Research on suppression effect of injection intensity distribution on high frequency longitudinal combustion instability

• Received:2021-06-25 Revised:2021-09-27 Online:2021-10-09 Published:2021-10-09

Abstract: Radial Injection intensity distribution has been adopt in many liquid rocket engines using storable hypergolic propellants, which has been one of the most important suppression methodsof combustion instability in engineer for these engines, except for acoustic damping devices. However, these engines still confront with some risk of combustion instability, which means that deep study on its suppression effect is still necessary. With the idea of independent injector, a model combustion chamber with impingement injectors of hypergolic propellant was designed and experimental study on high frequency longitudinal combustion instability of different injection intensity distribution was conducted. It is indicated that, for the case that droplet evaporation act as the rate controled process, enhancing injection intensity of the ‘hump zone’ are able to improve the high frequency longitudinal combusiton stability, whereas the improvement effect is depend on the relative result of the variation of combustion characteristic length and chamber length. Compare with the short case, in the case with long combustion chamber, the relative result of the variation of combusiton characteristic length due to the change of injection intensity distribution and combusiton chamber length will be smaller, and the correspond suppression effect will be weakened. Compare with the lower pressure case, evaporation of propellant droplets will accerate in high pressure case and mixture efficiency will be improved. which means that the way to control combustion distribution through much bigger droplets in high intensity zone will be weakened and suppresion effect will be reduced at the same time. For the case with high chamber pressure and long chamber length, high amplitude pressure oscillation is excited for each injector, and distribution of amplitudes has no relation with the injcetion intensity in hump zone.