某轴流风机噪声特性与降噪研究

Research on noise characteristics and noise reduction of axial fan

为实现某款车载方舱轴流风机的降噪,进行了轴流风机噪声特性研究。基于RNG k-ε模型、大涡模拟模型和FW-H噪声模型,运用滑移网格法和多重参考系法(Multiple reference frame,MRF),从稳态和瞬态两个维度对风机的偶极子噪声进行了数值模拟。结果显示:风机的噪声声压级为45.6 dB;在安装风机罩后,数值增大到59.2 dB。采用调整风机罩安装距离和出风口形状进行了降噪研究,研究表明:风机罩安装距离增加到25 mm时,噪声从59.2 dB降低到了51 dB;风机罩出风口改为扇形结构后,噪声从59.2 dB降低到了53.8 dB,降低了9.1%,降噪效果明显。

In order to realize the noise reduction of a certain vehicle modification shelter axial fan,the noise characteristics of the axial fan are studied.Based on RNG k-εmodel,large eddy simulation model and FW-H noise model,using sliding mesh method and Multiple Reference Frame(MRF)method,the dipole noise of the fan is simulated from two dimensions of steady state and transient state.The results show that the noise sound pressure level of the fan is 45.6 dB;After the fan cover is installed,the value increases to 59.2 dB.The noise reduction is studied by adjusting the installation distance of the fan cover and the shape of the air outlet.The research shows that the noise is reduced from 59.2 dB to 51 dB when the installation distance of the fan cover is increased to 25 mm;After the fan cover air outlet is changed into a fan structure,the noise is reduced from 59.2 dB to 53.8 dB,a reduction of 9.1%,and the noise reduction effect is obvious.