全尺寸短舱排气道声衬声学设计与试验验证  

Acoustic design and experimental verification of full-scale nacelle exhaust duct liner

作　　者：霍施宇[1] 杨嘉丰 邓云华 燕群[1] HUO Shiyu;YANG Jiafeng;DENG Yunhua;YAN Qun(Aviation Science and Technology Key Laboratory of Aeronautical Acoustics and Vibration,Aircraft Strength Research Institute of China,Xi'an 710065,China;Aeronautical Key Laboratory for Welding and Joining Technologies,AVIC Manufacturing Technology Institute,Beijing 100024,China)

机构地区：[1]中国飞机强度研究所航空声学与振动航空科技重点实验室,西安710065 [2]中国航空制造技术研究院航空焊接与连接技术航空科技重点实验室,北京100024

出　　处：《航空学报》2022年第6期512-520,共9页Acta Aeronautica et Astronautica Sinica

基　　金：民机专项(MJ-2016-G-66)。

摘　　要：针对排气道声衬应用环境,提出了一种适用于短舱排气道声衬的声学设计方法,利用有限元方法建立了排气道声衬声阻抗参数优化模型,根据设计工况和结构约束条件,设计并制备了一套全尺寸排气道内壁声衬试验件。为了验证排气声衬的声学设计方法,研发了频率范围500~16000 Hz、最大周向15阶模态的全尺寸声衬声学试验平台用以模拟风扇后传噪声特征,分别进行了声衬条件和固壁条件下辐射声场3 m和5 m处的指向性测试,获取了500~1500 Hz频率范围内的降噪量,试验结果表明设计声衬在950、1000 Hz频率点的降噪效果最优,充分验证了声衬设计的准确性。分析了设计工况下的声衬在3 m和5 m处辐射声场指向性的声压级分布,试验结果表明0°~90°范围内的最大降噪量分别为10.44 dB和7.21 dB。提出的排气道声衬声学设计与验证方法可为发动机短舱排气道声衬设计与验证提供重要技术支撑。An acoustic design method for nacelle exhaust duct acoustic liner is proposed based on the application environment of exhaust duct acoustic liner.An acoustic impedance parameter optimization model of exhaust duct acoustic liner is established using the finite element method.According to the design conditions and structural constraints,we design and prepare a set of full-scale exhaust duct inner wall acoustic liner simulation test pieces.To verify the acoustic design method for the exhaust sound liner,a full-scale sound liner acoustic test platform with a frequency range of 500-16000 Hz and a maximum circumferential 15 th order mode is developed to simulate the noise characteristics of fan back propagation.The directivity tests at 3 m and 5 m downstream of sound propagation under the sound liner and solid wall conditions are performed,respectively,and the noise reduction in the range of 500-1500 Hz is obtained.The test results show that the optimal noise reduction effect of the designed sound liner is reached at the frequency of 950 Hz and 1000 Hz,fully verifying the accuracy of the acoustic liner design.The sound pressure level distribution of the directivity of the radiated sound field at 3 m and 5 m of the sound liner under the design condition is analyzed,and the test results show the maximum noise reduction in the range of 0°-90°being 10.44 dB and 7.21 dB,respectively.The proposed acoustic design and verification method for exhaust duct acoustic liner can provide important technical support for the design and verification of exhaust duct acoustic liner of engine nacelles in China.

关 键 词：发动机短舱 排气道声衬 声学设计 声学试验 降噪量 辐射声场 

分 类 号：V231[航空宇航科学与技术—航空宇航推进理论与工程]