回流燃烧室小弯管双层壁流量系数及冷却特性试验

Experiment on Discharge Coefficient and Cooling Characteristics of Double-Wall of Concave Wall in Reverse Flow Combustor

关键词:  回流燃烧室  小弯管  冲击冷却  流量系数  冷却特性

Key words:  Reverse flow combustor  Concave wall  Impingement cooling  Discharge coefficient  Cooling characteristics

摘要:

为获得耦合参数（冲击孔径d_i，冲击孔流向间距S，冲击孔展向间距P）、小弯管外壁曲率半径（R₁，R₂）对回流燃烧室小弯管双层壁结构无量纲化流量系数C_d/C_d，max及无量纲化冷却效率η/η_max的影响规律，设计了4组共16个方案开展了实验研究。结果表明：S/P和R₁/R₂对于C_d/C_d，max的影响较小；随着S/P的增大，η/η_max呈先增后减的趋势，在S/P=0.8时达到最大值；随着R₁/R₂的增大，η/η_max呈增大的趋势；随着S/d_i和P/d_i的增大，C_d/C_d，max和η/η_max呈减小的趋势。

Abstract:

In order to obtain the effects of coupling parameters （impingement aperture d_i， impingement spacing of flow direction of impingement hole S， spacing of span direction of impingement hole P）， concave wall outer wall radius of curvature （R₁， R₂） on dimensionless discharge coefficient C_d/C_d，max and dimensionless cooling efficiency of double wall structure with concave wall in reverse flow combustor η/η_max ，four groups of sixteen schemes were designed to carry out experimental research. The results show that S/P and R₁/R₂ have little effect on C_d/C_d，max. With the increase of S/P， η/η_max shows a trend of increasing first and then decreasing， reaching the maximum value when S/P=0.8. With the increase of R₁/R₂， η/η_max shows an increasing trend. With the increase of S/d_i and P/d_i， C_d/C_d，max and η/η_max show a decreasing trend.