CAJ | 학술논문

目的针对实际的具有行波的管道模型,研究一种降噪方案.方法通过建立数学模型和用来导出降噪的自适应系统的传递函数,对RLS、LMS和LSL算法的效果进行分析和比较.结果不存在声反馈时,对0-500Hz的宽带噪声可达到平均降噪量(MNRV)27.5dB.若存在声反馈并使用气流扬声器时,MNRV只有近似4.9dB.当该扬声器具有平坦特性时,MNRV可提高10.2dB.结论这项抵消技术可用于对排气管降噪.原则上,它亦可用于三维封闭空间的降噪问题.
목적침대실제적구유행파적관도모형,연구일충강조방안.방법통과건립수학모형화용래도출강조적자괄응계통적전체함수,대RLS、LMS화LSL산법적효과진행분석화비교.결과불존재성반궤시,대0-500Hz적관대조성가체도평균강조량(MNRV)27.5dB.약존재성반궤병사용기류양성기시,MNRV지유근사4.9dB.당해양성기구유평탄특성시,MNRV가제고10.2dB.결론저항저소기술가용우대배기관강조.원칙상,타역가용우삼유봉폐공간적강조문제.
Aim To study a method realizing noise control for a physical model of progressive wave in a duct. Methods A mathematical model was constructed and a transfer function of the adaptive system for noise control was also worked out; moreover, the effects of some algorithms such as RLS,LMS and LSL on noise control were analyzed and compared. Results Without the feedback of sound, the mean noise reduce value(MNRV) of 27.5 dB for broadband noise from 0 to 500Hz in frequency were achieved. When acoustic feedback took place and an air-stream loudspeaker was used, the MNRV was only about 4.9dB. But if the loudspeaker had a plain frequency feature, MNRV was improved by 10.2dB. Conclusion The technique is applied to ruducing the noise from engines' exhausted gas pipes. It is, in principle, used for noise-cancelling in a closed three dimensional space.