大型离心式风机变工况调节中噪声特性的实验研究

目前大型电站使用的离心风机普遍存在噪声高的缺点,降低噪声已成为环保要求的迫切问题。针对G4-73No.8D大型离心式风机分别进行了出口节流调节、导流器调节和变速调节3种方式下的噪声特性实验研究,得到了变工况下的噪声特性曲线。实验表明,当流量减小时,出口节流调节下的噪声总体有所升高;导流器调节下的噪声总体呈小幅度的降低,但在某些导流器开度下噪声反而有所提高;变速调节下的噪声有大幅度的降低,噪声得到有效控制。从降低噪声和经济性方面考虑,变速调节的综合性能最优。

Experimental Study of Noise Characteristics of a Large-sized Centrifugal Fan During its Off-design Regulation Process

Nowadays,the centrifugal fans used in large-sized power plants universally suffer from a high noise level.Noise reduction has become a pressing task in environmental protection.An experimental study of noise characteristics of a Model G4-73No.8D large-sized centrifugal fan was conducted in three respects: outlet throttle regulation,flow-guide regulation and variable speed regulation.Noise characteristic curves under off-design conditions were obtained.The experiments show that when the flow rate falls,the noise level under the outlet throttle regulation mode will rise somewhat and that under the flow guide regulation mode fall slightly.But,by contrast,the noise level at certain opening degrees of the flow guide will somehow go up and that under the variable speed regulation mode will drop by a great margin,thus making it possible to effectively control the noise level.When viewed from the aspect of noise reduction and cost-effectiveness,the variable speed regulation offers an optimum overall performance.