Secondary source near-field error acquisition method suitable for pipeline active noise reduction

The invention discloses a secondary source near-field error acquisition method suitable for pipeline active noise reduction. When the active noise reduction system in the rectangular pipeline is compactly arranged (the distance from the secondary source to the error microphone is smaller than three times of the pipe diameter), the method can be used for obtaining high-quality low-frequency error signals in the near field of the secondary source, and the noise reduction effect below the cut-off frequency of the pipeline is effectively improved. 本发明公开了一种适用于管道有源降噪的次级源近场误差获取方法。当矩形管道中的有源降噪系统紧凑布放时(次级源到误差传声器距离小于3倍管径)，使用该方法可在次级源近场获得高质量的低频误差信号，有效提高管道截止频率以下的降噪效果。