【作者】 吕亚东； 余永祥； 胡宗安； 孙晓峰；

【Author】 Lu Ya-dong~1 Yu Yong-xiang Hu Zong-an Sun Xiao-feng~2 1.Institute of Acoustics,Academia Sinica,Beijing 100080,China 2.Beijing University of Aeronautics and Astronautics,Beij ing 100083,China

【机构】 中国科学院声学研究所； 北京航空航天大学；

【摘要】 干线飞机发动机短舱的消声设计有赖于发动机管内声场(包括从声源发声到管内传播)预测体系的建立。为此,本文在提出转/静干涉噪声声源模态和管内传播模态之间的声学匹配理论基础上,建立了转/ 静干涉噪声发声及其在敷设多段声衬圆环形管道内传播、衰减的理论预测方法。该方法的建立在一定程度上克服了过去多段声衬管内声传播模态分析预测对于管内模态试验测量的依赖,这样管道内声传播、声衰减模态分析研究不仅可以通过声学模态测量来进行,而且可以通过声源理论预测以确定转/静干涉噪声声源模态来实现。应用该预测方法对风扇转速、转/静子叶片数、转/静子轴向间距对管内噪声衰减量和管道前后总声功率级(也包括叶片通过频率各阶谐波声功率级)的影响进行了算例计算,并与文献测试数据进行了对比和验证。通过算例结果分析,为发动机短舱的消声设计提供了若干工程设计参考准则。更多还原

【Abstract】 The suppressing design of engine nacelle in a aircraft can benefit from the development of the prediction system for sound fields in engine ducts which cover the source generation and sound propagation.Firstly,the acoustic mode matching theory between the source modes of rotor-stator interaction noise and the propagation modes is presented in this paper. Secondly,by utilizing this theory,the theoretical prediction method of rotor-stator interaction noise generation and it’s propagation and attenuation in an annular duct with multi-treatments is developed.That means that the prediction of sound propagation and attenuation in the segmented ducts might no longer completely depend on the in-duct mode measurements,and the investigation on the sound propagation and attenuation in ducts can be accomplished not only by acoustic mode measurement,but also by making use of the source prediction to determine the source modes excited by rotor-stator interaction.The effects of fan speed,blade/vane numbers,axial spacing between rotor and stator on the in-duct sound attenuation and generated sound power level have been numerically calculated by using this prediction system.The reliability of this prediction method is verified by good agreement between the predicted results with measured results of references. By analyzing the results of calculating cases,some reference criteria are,provided for the engineering design of the suppressing engine nacelle.更多还原