ATR发动机燃烧室波瓣混合器张角及瓣宽比对掺混、燃烧特性的影响

Effects of Penetration Angle and Width Ratio of Lobed Mixer on Mixing and Combustion Performance in ATR Combustors

关键词:  ATR发动机  波瓣混合器  掺混  燃烧  流向涡

Key words:  ATR engine  Lobed mixer  Mixing  Combustion  Streamwise vortex

摘要:

为了促进空气涡轮火箭发动机燃烧室内来自压气机的空气和流经涡轮的富燃燃气的掺混与燃烧，基于空气涡轮火箭发动机燃烧室入口结构参数设计了波瓣混合器，并采用数值模拟方法通过调整张角及瓣宽比对波瓣结构进行优化。结果表明：（1）保持外张角不变，增大波瓣内张角可以有效改善内涵燃料在燃烧室中心轴附近区域燃烧不完全的状况；（2）在内、外张角相同的条件下，通过减小瓣宽b₂使瓣宽比Bˉ大于1可以提升掺混及燃烧效率；（3）相对于非反应流动，波瓣诱导流向涡在反应流中强度更高，沿径向向外移动的速度也更快；（4）带有波瓣结构的燃烧室内，因内、外涵气流掺混造成的总压损失很小，80%以上的总压损失是由加热造成的。

Abstract:

The lobed mixers were designed based on the ATR combustor inlet structure to facilitate the mixing and combustion of the air from the compressor and the fuel-rich gas from the turbine， and the numerical methods were used. The structure of lobe was optimized by increasing the penetration angle and the lobe width ratio. The relevant results show that： （1） Keeping the inner penetration angle constant and increasing the inner penetration angle， the status of incomplete combustion in the center area of the combustor can be alleviated effectively. （2） Keeping the inner and outer penetration angles constant and decreasing the lobe width b₂ at the trailing edge so that the lobe width ratio Bˉ is less than 1 can increase the mixing and combustion efficiencies. （3） Compared with the non-reacting flow， the streamwise vortex induced by the lobed mixer has higher intensity and radial velocity in the reacting flow. （4） In combustors with the lobed mixers， the total pressure loss caused by the mixing between the core and bypass flows is small， more than 80% of total pressure loss is caused by the heating process.