首页 | 本学科首页   官方微博 | 高级检索  
     

提高背景噪声下结构辐射声强测量精度的研究
引用本文:胡章伟,尹坚平.提高背景噪声下结构辐射声强测量精度的研究[J].振动工程学报,1992,5(2):91-97.
作者姓名:胡章伟  尹坚平
作者单位:南京航空学院空气动力学系,南京航空学院空气动力学系,南京航空学院空气动力学系 南京 210016,南京 210016,南京 210016
摘    要:背景噪声存在会引起薄壁结构表面辐射声强和声功率的测量误差。将探头屏蔽起来是降低这一误差的方法之一。本文分别对两种声屏蔽罩和局部声屏蔽空间进行了研究。结果表明,屏蔽罩虽然使用方便,但对薄壁结构表面声辐射这类抗性很强的声场.它的放入将破坏局部声场,引起测量的偏度误差,不宜采用。就本身声学特性来说.吸声材料构成实心锥的声屏蔽罩明显优于空心锥形的.在被测声场抗性不强的情况下可以采用。本文提出的局部声屏蔽空间解决了声屏罩引起的问题,当背景噪声的总声压级比信号的总声压级高出10dB时,总声强的测量误差低于1dB,声强细谱的误差小于2dB,有效地抑制了背景噪声引起的声强测量误差。

关 键 词:噪声测量  声强  结构声辐射  声屏蔽

Improving Measurement Accuracy of Structure Sound Radiation Intensity under Background Noise
Hu Zhangvuei Yin Jianping Zhang Qiang.Improving Measurement Accuracy of Structure Sound Radiation Intensity under Background Noise[J].Journal of Vibration Engineering,1992,5(2):91-97.
Authors:Hu Zhangvuei Yin Jianping Zhang Qiang
Abstract:Acoustic shading of intensity probe is a way of suppressing intensity measurement error dure to background noise. Two acoustic shades, one with concave absorber and the other with convex absorber have been studied. The results indicate that these shades are improper for measuring intensity of sound radiated from a thin walled structural surface, which has strong reactive sound field. The shade with convex absorber is superior to that with concave absorber in acoustic property and can be used to measure intensity in the less reactive sound field. An acoustically shielded space with cross dimensions larger than the measured surface. which consists of a 50mm thick fibreglass curtain, is proposed. The test results indicate that it is satisfied for the intensity measurement in a strong background noise environment.
Keywords:nosie measurement  sound intensity measurement  structural sound radiations  acoustic shading
本文献已被 CNKI 维普 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号