一、前言我国的风机消声器虽然已经有不少定型产品,但大多数低频消声效果较差。一般250赫和500赫的插入损失,不到20～25分贝。而这2个频率却正是我国电机通常的运行频率(1450转/分和2900转/分),即风机的基频所在,噪声都比较高,因而大大地影响了消声器的实际使用效果。提高这2个频率的消声量,是改进消声器 First, the preface China’s fan muffler Although there are many stereotypes, but most of the low-frequency muffler less effective. Generally 250 Hz and 500 Hz insertion loss, less than 20 ~ 25 dB. However, these two frequencies are just the normal operating frequency of our motor (1450 rpm and 2900 rpm), that is, the fundamental frequency of the fan is high and the noise is relatively high, thus greatly affecting the practical effect of the muffler. Improve the muffler volume of these two frequencies is to improve the muffler