主流压力梯度对气膜孔流量系数影响机理

朱惠人; 骆剑霞; 黄小杨; 刘志刚

doi:10.13224/j.cnki.jasp.2014.09.018

主流压力梯度对气膜孔流量系数影响机理

doi: 10.13224/j.cnki.jasp.2014.09.018

西北工业大学动力与能源学院, 西安 710072

基金项目:

国家重点基础研究发展计划（2013CB035702）

详细信息

作者简介:
朱惠人（1958-），男，陕西西安人，教授、博士生导师，博士，主要从事航空宇航气动传热方向的研究.

中图分类号: V231.1
计量
- 文章访问数: 1291
- HTML浏览量: 0
- PDF量: 860
- 被引次数: 0
出版历程
- 收稿日期: 2013-06-16
- 刊出日期: 2014-09-28

Influence physics of mainstream pressure gradient on film hole discharge coefficient

School of Power and Energy, Northwestern Polytechnical University, Xi'an 710072, China

摘要

摘要: 测量了主流零压力梯度、正压力梯度及负压力梯度条件下气膜孔流量系数，分析了主流压力梯度对气膜孔流量系数的影响机理.结果显示：正、负压力梯度的存在对气膜孔流量系数的影响幅度最大值分别为22%及26%.主流压力梯度会对喷出气流施加弯转作用及挤压作用，同时也会改变喷出气流与近壁面主流的掺混作用，从而影响气膜孔流量系数.挤压作用使喷出气流管变细而增加喷出气流的流动损失；弯转作用主要影响喷出气流的流动轨迹，正压力梯度下弯转作用使喷出气流的轨迹靠近壁面而远离其自由喷射方向增加流动损失，负压力梯度的作用则相反；掺混作用会增加喷出气流的动量消耗，正压力梯度对掺混有抑制作用，从而减少喷出气流用于掺混的动量损失，负压力梯度则相反.
- 推进系统 /
- 压力梯度 /
- 燃气涡轮 /
- 流量系数 /
- 气膜孔
Abstract: Film hole discharge coefficients at different mainstream pressure gradients (zero pressure gradient, positive pressure gradient and negative pressure gradient) were tested, and influence physics of mainstream pressure gradient on film hole discharge coefficient was analyzed. Result shows that the maximum amplitude of effect on film hole discharge coefficient of mainstream positive and negative pressure gradients are 22% and 26% respectively. At different mainstream pressure gradients, bending effect and crushing effect of mainstream on jet are different, together with the changed interaction of jet with mainstream, and therefore the film hole discharge coefficient will be different. Crushing effect makes jet narrower and enhances the jet flow loss. Bending effect can change jet flow track; the positive pressure gradient makes jet flow close to the wall but far away from the free ejection direction, resulting in more flow loss; to the contrary, the negative pressure gradient may decrease the flow loss. The mixing effect enhances the momentum dissipation of jet, while at positive pressure gradient, the mixing effect is restrained and then momentum dissipation of jet decreases, however, the rule is opposite at negative pressure gradient.
- propulsion system /
- pressure gradient /
- gas turbine /
- discharge coefficient /
- film hole

HTML

参考文献(15)

[1]	Hay N,Spencer A.Discharge coefficients of cooling hole with radiused and chamfered inlet[J].Journal of Turbomachinery,1992,114(4):701-706.
[2]	Hay N,Lampard D,Khaldi A.The coefficients of discharge of 30 degree inclined film cooling holes with rounded entries or exits[R].ASME Paper 94-GT-180,1994.
[3]	Burd S W,Simon T W.Measurements of discharge coefficients in film cooling[J].Journal of Turbomachinery,1999,121(2):243-248.
[4]	Hay N,Lampard D.The discharge coefficient of flared film cooling holes[R].ASME Paper 95-GT-15,1995.
[5]	朱惠人,许都纯,刘松龄.气膜孔形状对流量系数影响的实验研究[J].推进技术,1998,19(1):42-45. ZHU Huiren,XU Duchun,LIU Songling.The experimental investigation in the effects of film cooling holes shape on discharge coefficient[J].Journal of Propulsion Technology,1998,19(1):42-45.(in Chinese)
[6]	杨卫华,马国锋,张靖周,等.气膜孔几何结构对流量系数的影响[J].推进技术,2005,26(5):413-416. YANG Weihua,MA Guofeng,ZHANG Jingzhou,et al.Influence of geometrical construction of film cooling hole on discharge coefficient[J].Journal of Propulsion Technology,2005,26(5):413-416.(in Chinese)
[7]	Gritsch M,Schulz A,Wittig S.Discharge coefficient measurements of film-cooling holes with expanded exits[J].Journal of Turbomachinery,1998,120(3):557-563.
[8]	Makki Y H,Jakubowski G.An experimental study of film cooling from diffused trapezoidal shaped holes[R].AIAA 86-1326,1986.
[9]	Gritsch M,Saumweber C,Schulz A,et al.Effect of internal coolant crossflow orientation on the discharge coefficient of shaped film-cooling holes[J].Journal of Turbomachinery,2000,122(1):146-152.
[10]	Roger T,Hersh A S.The effect of grazing flow on the steady state resistance of squared-edged orifices[R].AIAA 75-493,1975.
[11]	Hay N,Lampard D,Benmansour S.Effect of crossflows on the discharge coefficient of film cooling holes[J].Journal of Engineering for Power,1983,105(2):243-248.
[12]	Gritsch M,Schulz A,Wittig S.Effect of crossflow on the discharge coefficient of film cooling holes with varying angles of inclination and orientation[J].Journal of Turbomachinery,2001,123(4):781-787.
[13]	Rowbury D A,Oldfield M L G,Lock G D.Engine representative discharge coefficients measured in an annular nozzle vane cascade[R].ASME Paper 97-GT-99,1997.
[14]	Rowbury D A,Oldfield M L G,Lock G D.Large-scale testing to validate the influence of external crossflow on the discharge coefficients of film cooling holes[J].Journal of Turbomachinery,2001,123(4):593-600.
[15]	邓明春,朱惠人,王学文,等.密度比对涡轮叶片气膜孔流量系数的影响[J].航空动力学报,2006,21(5):796-799. DENG Mingchun,ZHU Huiren,WANG Xuewen,et al.Influence of density ratio on the discharge coefficient of turbine blade film cooling holes[J].Journal of Aerospace Power,2006,21(5):796-799.(in Chinese)