发散孔结构参数对横向波纹表面气膜绝热冷却效率的影响  

Effects of structural parameters of effusion holes on adiabatic film cooling effectiveness over transverse corrugated surface

作　　者：渠立红 张靖周 谭晓茗 QU Lihong;ZHANG Jingzhou;TAN Xiaoming(Jiangsu Province Key Laboratory of Aerospace Power System, College of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;Collaborative Innovation Center for Advanced Aero-Engine, Beijing 100191, China)

机构地区：[1]南京航空航天大学能源与动力学院江苏省航空动力系统重点实验室,南京210016 [2]先进航空发动机协同创新中心,北京100191

出　　处：《航空动力学报》2018年第3期590-596,共7页Journal of Aerospace Power

基　　金：国家自然科学基金(U1508212);航空科学基金(2015ZB52019)

摘　　要：针对加力燃烧室特定横向波纹结构的隔热屏发散冷却进行数值模拟,主要研究发散孔孔节距、孔径以及开孔率等3个结构参数对发散冷却效率的影响。结果表明:由于处于波纹波谷的相邻气膜射流更易于形成相干,从而在波谷形成更强的集聚效应,造成波谷附近的绝热壁面温度低于波峰区域;在相同的壁面单位面积冷气用量下,减小孔径、增大开孔率均显著改善气膜冷却效率,尤其是在发散气膜的前排起始段;发散孔流向节距大于展向节距的长菱形排布相对较优,但在小吹风比下发散孔排布节距比对展向平均绝热冷却效率的影响非常微弱。Numerical simulation was carried out to study the effusion cooling on a specific transverse corrugated heat-shield used in aero-engine afterburner.Three main geometric parameters,including spanwise-to-streamwise pitch ratio,hole diameter and perforated percentage,were taken into consideration.Result showed that,in the wavy valley of transverse corrugated surface,the coolant jets ejected from adjacent holes were prone to interact each other,thus forming more coolant accumulation.Due to this feature,the adiabatic wall temperature on the wavy valley of transverse corrugated surface was relatively lower than that on the wavy peak.In general,reducing the hole diameter and enlarging the perforated percentage were illustrated to be significantly helpful to enhance the film cooling effectiveness under the same coolant usage for a given protected area,especially in the front developing zone of an effusion cooling scheme.Besides,the effusion holes arranged in a super-long-diamond mode where the streamwise hole-to-hole pitch was bigger than spanwise hole-to-hole pitchshowed more favorable.However,the effect of spanwise-to-streamwise pitch ratio on the laterally-averaged adiabatic film cooling effectiveness was very weak at low blowing ratio.

关 键 词：横向波纹 隔热屏 发散冷却 结构参数 气膜冷却效率 

分 类 号：V231.1[航空宇航科学与技术—航空宇航推进理论与工程]