摘要
本文设计了一种尾缘(TE)上游多孔渗透结构,通过在全消声低速射流风洞,利用远场麦克风测量研究了不同工况和材料物性下尾缘辐射噪声的影响。结果表明:所设计的多孔渗透结构产生了额外的方腔噪声特征,相对密度4.7%的泡沫金属所产生的附加噪声最小,颗粒状多孔材料比泡沫金属产生的附加噪声小。对称流动条件下多孔平板尾缘噪声中出现的方腔单音噪声特征,在人工非对称流动条件干涉下消失,表明压差推动渗流穿过表面是这种设计的关键。缩小人工非对称流动与非对称曲面翼型产生的压力条件之间的差异以及避免过大面积多孔设计是改进的方向。
A novel porous permeable section of the trailing edge（TE）is designed and tested in acoustics wind tunnel using far-field microphone to investigate the effects of various flow conditions and material properties on the TE noise.The results show that the current porous permeable section causes extra cavity noise component.The 4.7% relative density of metal foam causes the minimum extra noise,and the granular porous materials produces less extra noise than that of metal foam.Under the symmetrical flow condition,the TE noise of porous flat plate contains the cavity tonal component which disappears under the artificial nonsymmetrical flow condition.It indicates that the pressure difference pushing the airflow pass through the porous surface is crucial for the design of the porous section.It is found that reducing the discrepancy of pressure distribution between artificial nonsymmetrical flow and practical nonsymmetrical airfoil,as well as reducing the excessive porous area,should be focused on during the design of porous section for TE noise reduction.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2017年第6期32-42,共11页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(51506179)
中央高校基本科研业务费专项资金(3102016ZY018)~~
关键词
翼型噪声
多孔材料
气动声学
人工压差
声学风洞
airfoil noise
porous materials
aeroacoustics
artificial pressure difference
acoustics wind tunnel
