不同间隙大小轴流压气机转子叶尖泄漏非定常流动的DDES研究（英文）  

Unsteady Behavior of Tip Leakage Vortex in an Axial Compressor with Different Rotor Tip-gap Sizes Using DDES

作　　者：钟路阳 柳阳威 陆利蓬 Lu-yang Zhong;Yang-wei Liu;Li-peng Lu

机构地区：[1]National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing, China [2]Collaborative Innovation Center of Advanced Aero-Engine, Beihang University, Beijing, China

出　　处：《风机技术》2019年第2期1-9,I0006,共10页Chinese Journal of Turbomachinery

基　　金：The National Natural Science Foundation of China(No.51376001,No.51676007,No.51420105008);the National Basic Research Program of China(No.2014CB046405)

摘　　要：叶尖泄漏流动对航空发动机的压气机性能有很大的影响,对其进行准确的数值模拟十分重要。延迟脱落涡模拟(DDES)方法在保证计算准确性的同时节省了计算资源。本文针对不同间隙大小和不同工况对大尺寸低速轴流压气机转子进行了DDES 模拟。将时均结果与瞬时结果进行了比较,分析了不同叶尖尺寸下流动的非定常性。然后利用LUMLEY 三角形分析了叶尖泄漏流动的雷诺应力各向异性。各向异性沿叶尖泄漏涡向下游发展方向变化。小间隙情况下各向异性较弱,这是由于小间隙情况下流动更加稳定。最后,利用快速傅里叶变换(FFT)分析了泄漏涡核心的速度脉动频谱,讨论了泄漏流动的非定常性。Tip leakage flow (TLF) has a large impact on compressor performance and should be accurately predicted by CFD methods. New approaches to turbulence modelling, such as delayed detached eddy simulation (DDES) have been proposed which allow for greater accuracy of the numerical predictions while computational resources can be tremendously reduced. In this paper, the numerical simulation of the rotor in a low-speed large-scale axial compressor based on DDES is performed subject to different operating conditions of different tip gap sizes. The time-averaged and instantaneous results are compared to analyze the unsteadiness in visual at different tip gap sizes. Then, the anisotropy of the TLF is analyzed through Lumley triangle. The anisotropy varies along the tip leakage vortex (TLV). The anisotropy of the small tip gap condition is weak because the flow at this condition is more stable. Last, the velocity fluctuation data along the TLV are transformed to velocity spectra using fast Fourier transformation (FFT) method to discuss the TLV unsteadiness.

关 键 词：叶尖泄漏涡 压气机转子 小间隙 非定常流动 轴流 应力各向异性 快速傅里叶变换 泄漏流动 

分 类 号：V231.3[航空宇航科学与技术—航空宇航推进理论与工程]