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为验证不同温度条件下的传热传质类比是否有效,应用CFD模拟方法分析了密度比(Rd)为1.5和2.5、吹风比为0.5和1.5工况下的平板双射流气膜冷却结构。双射流孔间流向距离(Ds/d)为3.0,横向距离(Dp/d)为1.0。通过传热和传质方法分别得到了气膜冷却效率。分析结果表明:传质方法与传热方法所获得的气膜冷却效率结果差距较小,二者偏差的主要原因是流体的热导率。

CFD simulation methods were employed to analyze the double-jet film-cooling structure on a flat plate with the density ratio of 1.5 and 2.5, and the blowing ratio of 0.5 and 1.5, in order to check the validity of heat-mass transfer analogy at different temperature conditions. The streamwise distance(Ds/d)between the double-jet holes was 3.0 and the spanwise distance(Dp/d)was 1.0. The film-cooling effectiveness was acquired from heat-transfer and mass-transfer methods. The results show that, the difference in film-cooling effectiveness results from mass transfer and heat transfer methods is rather small. The main reason that leads to the difference between the two methods is the heat conductivity of the fluid.

引言
1 数值方法
2 结果与讨论
3 结论

表1 符号、含义及单位<br/>Tab.1 Symbol,meaning and unit

表1 符号、含义及单位
Tab.1 Symbol,meaning and unit

图1 计算域与气膜孔附近网格<br/>Fig.1 The computational domain and the mesh around the film holes

图1 计算域与气膜孔附近网格
Fig.1 The computational domain and the mesh around the film holes

图2 三维几何模型与气膜孔结构<br/>Fig.2 3—D geometry model and the structure of the film holes

图2 三维几何模型与气膜孔结构
Fig.2 3—D geometry model and the structure of the film holes

表2 Rd=1.5计算工况<br/>Tab.2 Rd=1.5 operation conditions 单位:K

表2 Rd=1.5计算工况
Tab.2 Rd=1.5 operation conditions 单位:K

表3 Rd=2.5计算工况<br/>Tab.2 Rd=2.5 operation conditions 单位:K

表3 Rd=2.5计算工况
Tab.2 Rd=2.5 operation conditions 单位:K

图3 网格无关性验证及模拟与实验对比<br/>Fig.3 Grid—independence validation and comparison between simulations and experiments

图3 网格无关性验证及模拟与实验对比
Fig.3 Grid—independence validation and comparison between simulations and experiments

图4 Yao J等的实验设备<br/>Fig.4 The experimental setup of Yao J et al.

图4 Yao J等的实验设备
Fig.4 The experimental setup of Yao J et al.

图5 壁面(z=0)气膜冷却效率分布与横向平均冷却效率<br/>Fig.5 Film—cooling effectiveness distribution on the wall(z=0)and laterally averaged cooling effectiveness

图5 壁面(z=0)气膜冷却效率分布与横向平均冷却效率
Fig.5 Film—cooling effectiveness distribution on the wall(z=0)and laterally averaged cooling effectiveness

图6 x/d=5.0时空间气膜分布与横向冷却效率分布<br/>Fig.6 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

图6 x/d=5.0时空间气膜分布与横向冷却效率分布
Fig.6 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

图7 壁面(z=0)气膜冷却效率分布与横向平均冷却效率<br/>Fig.7 Film—cooling effectiveness distribution on the wall (z=0)and laterally averaged cooling effectiveness

图7 壁面(z=0)气膜冷却效率分布与横向平均冷却效率
Fig.7 Film—cooling effectiveness distribution on the wall (z=0)and laterally averaged cooling effectiveness

图8 x/d=5.0时空间气膜分布与横向冷却效率分布<br/>Fig.8 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

图8 x/d=5.0时空间气膜分布与横向冷却效率分布
Fig.8 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

图9 壁面(z=0)气膜冷却效率分布与横向平均冷却效率<br/>Fig.9 Film—cooling effectiveness distribution on the wall (z=0) and laterally averaged cooling effectiveness

图9 壁面(z=0)气膜冷却效率分布与横向平均冷却效率
Fig.9 Film—cooling effectiveness distribution on the wall (z=0) and laterally averaged cooling effectiveness

图10 x/d=5.0时空间气膜分布与横向冷却效率分布<br/>Fig.10 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

图10 x/d=5.0时空间气膜分布与横向冷却效率分布
Fig.10 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

图11 壁面( z=0)气膜冷却效率分布与横向平均冷却效率<br/>Fig.11 Film—cooling effectiveness distribution on the wall (z=0)and laterally averaged cooling effectiveness

图11 壁面( z=0)气膜冷却效率分布与横向平均冷却效率
Fig.11 Film—cooling effectiveness distribution on the wall (z=0)and laterally averaged cooling effectiveness

图12 x/d=5.0时空间气膜分布与横向冷却效率分布<br/>Fig.12 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

图12 x/d=5.0时空间气膜分布与横向冷却效率分布
Fig.12 x/d=5.0, spatial film distribution and laterally cooling effectiveness distribution

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备注

引言

1 数值方法

2 结果与讨论

3 结论

期刊信息