二次冲击对静叶前缘冷却性能影响的对比研究  

A Comparative Study on the Effect of Second-Impingement on the Cooling Performance of Vane Leading Edge

作　　者：陈欣楠 李志刚[1] 李军[1] 徐庆宗 杜强[2] CHEN Xinnan;LI Zhigang;LI Jun;XU Qingzong;DU Qiang(Institute of Turbomachinery,Xi’an Jiaotong University,Xi’an 710049,China;Institute of Engineering Thermophysics,Chinese Academic of Sciences,Beijing 100190,China)

机构地区：[1]西安交通大学叶轮机械研究所,西安710049 [2]中国科学院工程热物理研究所,北京100190

出　　处：《西安交通大学学报》2023年第5期34-45,共12页Journal of Xi'an Jiaotong University

基　　金：国家科技重大专项资助项目(J2019-Ⅱ-0022-0043)。

摘　　要：为了进一步优化现代先进燃机高压涡轮静叶前缘区域的冷却性能,基于NASA C3X叶型建立了上游腔室采用冲击冷却与气膜冷却组合的阵列冲击-气膜复合冷却静叶模型,采用流固共轭传热方法数值研究了涡轮静叶内部冷气的流动和传热特性,针对常用的冷气流量范围分析了引入二次冲击结构对静叶前缘冷却性能的影响。结果表明:二次冲击对靶面对流换热影响较小,但能有效提高冷气在整个流路中的对流换热强度,还能平衡不同区域气膜孔排的冷气流量分配。二次冲击有效降低了气膜孔附近的固体温度,尤其是对于气膜孔较密集的前缘。同时,在固体导热的作用下,气膜孔附近的低温区会影响到无气膜孔区域,降低整个固体域的温度。二次冲击显著改善了叶片上游表面尤其是前缘的复合冷却性能,其中,对上游表面的优化率大体上随冷气流量的增大先升高后降低,在质量流量比M为1.25%时最高,约为4.44%;对前缘的优化率大体上随冷气流量的增大先降低后升高,在M为1.50%时最低,约为9.66%,在M为2.25%时最高,约为11.70%。To further optimize the cooling performance at the vane leading edge of the modern advanced high-pressure turbine,this paper establishes a NASA C3X turbine vane model in which the upstream chamber is subject to the array impingement-film composite cooling.Fluid-solid conjugate heat transfer analyses are conducted to numerically investigate the flow and heat transfer characteristics of the coolant inside the vane.The effect of second-impingement structure on the composite cooling performance of the leading edge is studied with the amount of coolant mass flux in the common range.The results show that the second-impingement has little effect on convective heat transfer of the target,but can enhance the convective heat transfer intensity of the coolant in the whole flow path.The second-impingement can also balance the distribution of coolant in film holes in different regions and effectively reduce the temperature of the solid domain near film holes,especially for the leading-edge area with the showerhead.Meanwhile,under the heat conduction of the solid domain,the low temperature area near film holes will affect the region nearby,causing a reduction in overall temperature.In addition,the second-impingement significantly improves the composite cooling of the vane surface,especially the leading edge.The optimizing effect on the upstream surface generally increases first and then decreases with the increase of the mass flux of coolant,reaching a highest value of about 4.44%when M is 1.25%.The optimizing effect on the leading edge generally decreases first and then increases with the increase of the mass flux of coolant,reaching a highest value of about 9.66%when M is 1.50%,and a lowest value of about 11.70%when M is 2.25%.

关 键 词：静叶前缘 共轭传热 冲击冷却 气膜冷却 

分 类 号：TK474.7[动力工程及工程热物理—动力机械及工程]