Journal of Propulsion Technology ›› 2021, Vol. 42 ›› Issue (3): 601-611.DOI: 10.13675/j.cnki.tjjs.200179

• Combustion, Heat and Mass Transfer • Previous Articles     Next Articles

Effects of Area Ratio of Film Hole to Impingement Hole and Momentum Flux Ratio on Overall Cooling Effectiveness of Afterburner Double Wall Heat Shield

  

  1. 1.School of Power and Energy,Northwestern Polytechnical University,Xi’an 710072,China;2.Shaanxi Key Laboratory of Thermal Sciences in Aero-Engine System,Northwestern Polytechnical University, Xi’an 710072,China;3.AECC Sichuan Gas Turbine Establishment,Chengdu 610500,China
  • Online:2021-03-15 Published:2021-08-15

气膜孔与冲击孔面积比和动量比对加力燃烧室双层壁隔热屏综合冷却效率的影响

牛嘉嘉1,2,刘存良1,2,刘海涌1,2,肖翔3,林建府3   

  1. 1.西北工业大学 动力与能源学院,陕西 西安 710072;2.西北工业大学 陕西省航空动力系统热科学重点实验室,陕西 西安 710072;3.中国航发四川燃气涡轮研究院,四川 成都 610500
  • 作者简介:牛嘉嘉,博士生,研究领域为航空发动机高温部件的传热与冷却。E-mail:niujiajia_nwpu@163.com
  • 基金资助:
    中央高校基本科研业务费专项资金(3102018zy019);陕西省创新能力支撑计划(2019KJXX-065)。

Abstract: The cooling effect can be effectively enhanced by using the impingement/effusion double wall cooling structure. According to the developing requirements of high efficient cooling performance of afterburner heat shield, based on analogy theory and matching principle for scaling overall cooling effectiveness, the overall cooling effectiveness distribution of afterburner double-wall heat shield were measured by using IR thermography. Effects of area ratios of film hole to impingement hole (Af/Ai=1,2,3,4) and momentum flux ratios (I=0.02~0.88) on the cooling characteristics were investigated experimentally. The results indicate that the overall cooling effectiveness distribution is determined by the impingement cooling, the film cooling, and the relative position of impingement hole and film hole. High overall cooling effectiveness appears in the region near the impingement stagnation point and covered by the film. Along the streamwise direction, the overall cooling effectiveness in the downstream region of film plate is higher than that in the upstream region. As the momentum flux ratio increases, the overall cooling effectiveness increases. With the increase of the area ratio of film hole to impingement hole, the overall cooling effectiveness in the upstream region of film plate mainly increased due to the enhancement of the impingement heat transfer, and the overall cooling effectiveness in the middle and downstream region of film plate increased due to the enhancement of impingement heat transfer and the film cooling effect. The area averaged overall cooling effectiveness increased by 72% with increasing the area ratio of film hole to impingement hole from 1 to 3, and the area averaged overall cooling effectiveness increased by 12% with increasing the area ratio of film hole to impingement hole from 3 to 4.

Key words: Afterburner;Heat shield;Impingement/effusion cooling;Area ratio;Overall cooling effectiveness

摘要: 利用冲击/发散双层壁冷却结构可以有效加强冷却效果。针对加力燃烧室隔热屏高效冷却性能的发展要求,基于综合冷却效率模化理论和匹配原则,采用红外测温技术测量了加力燃烧室双层壁隔热屏的综合冷却效率分布,分析了气膜孔与冲击孔面积比(Af/Ai=1,2,3,4)和动量比(I=0.02~0.88)等参数对加力燃烧室双层壁隔热屏冷却特性的影响规律。研究结果表明:综合冷却效率分布由冲击冷却、气膜冷却及冲击孔和气膜孔的相对位置决定。高冷效区域集中在冲击驻点附近和气膜覆盖的区域。沿着主流的流动方向,气膜板下游的综合冷却效率高于上游的综合冷却效率。随着动量比的增大,综合冷却效率增大。随着气膜孔与冲击孔面积比的增大,气膜板上游的综合冷却效率主要是由于冲击换热的增强而增大,气膜板中下游的综合冷却效率是由于冲击换热和气膜冷却效果的增强而增大。气膜孔与冲击孔面积比由1增大到3,面平均综合冷却效率提高72%,气膜孔与冲击孔面积比由3增大到4时,面平均综合冷却效率提高了12%。

关键词: 加力燃烧室;隔热屏;冲击发散冷却;面积比;综合冷却效率