The Effect of Four Part Gap Geometry Configurations for Variable Stator Vanes in a Compressor Cascade
The Effect of Four Part Gap Geometry Configurations for Variable Stator Vanes in a Compressor Cascade
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压缩机叶栅中可变定子叶片的四部分间隙几何结构的影响
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
R. Mailach
中科院分区：
文献类型：
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作者：
M. Gottschall;K. Vogeler;R. Mailach
本文采用数值模拟方法研究了四种不同端壁间隙的可调静叶对高压压气机二次流场发展和性能的影响。这项工作的目的是量化不同的间隙配置的特点取决于硬币轴的位置和硬币直径为一个典型的操作范围。所有的间隙配置都应用于现代定子型线的线性叶栅。分析采用了在三个安装角和两个特征雷诺数下1.3%弦长的相对间隙尺寸来模拟航空发动机的工作范围。对叶栅内部流场进行了三维数值计算。将它们与5孔探针的测量结果以及翼型和端壁上的压力分布进行了比较。计算流体动力学表明，对于较低的和标称的安装角，间隙特性与测量结果非常一致。叶片后部的小间隙对流场有有利的影响。相比之下，叶片的较高负载前部中的间隙总是导致损失增加。另外，计算流体动力学没有反映出后部间隙的显著增强性能，该性能是在较高的安装角下测量的。即使与没有间隙的配置相比，混合损失的减少和平均气流转向的增加也没有通过计算得到验证。与实验相比，在大安装角下的大流量分离导致计算流体动力学的欠转高出2至4倍。由于间隙和反向分离流的严重混合，间隙对特征径向损失分布的影响（高达40%的叶片高度）也与测量结果存在偏差。Copyright © 2012 by ASME
The article describes numerical investigations on the influence of four different endwall clearance topologies for variable stator vanes to secondary flow field development and the performance of high pressure compressors. The aim of this work is to quantify the characteristics of different clearance configurations depending on the penny-axis position and the penny diameter for a typical operating range. All clearance configurations were implemented to a linear cascade of modern stator profiles. The analysis was introduced using a relative clearance size of 1.3% chord at three stagger angles and two characteristic Reynolds numbers to model the operating range on aircraft engines. 3D numerical calculations were carried out to gain information about the flow field inside the cascade. They were compared with measurements of a 5-hole-probe as well as pressure tappings on the airfoil and the endwall.The CFD shows the clearance characteristics in good agreement with the measurements for the lower and the nominal stagger angle. Small gaps in the rear part of the vane have a beneficial effect on the flow field. In contrast, a clearance in the higher loaded front part of the vane always resulted in increased losses. Otherwise, the significant enhanced performance of a rear part gap, which was measured at the higher stagger angle, was not reflected by the CFD. The reduced mixing losses and the higher averaged flow turning even compared to a configuration without a clearance are not verified with the calculations. Large flow separations at the high stagger angle result in a two to four times higher underturning of the CFD in comparison to the experiments. The clearance effects to the characteristic radial loss distribution up to 40 % bladeheight also deviate from the measurements due to heavy mixing of clearance and reversed separated flow.Copyright © 2012 by ASME