双吸平衡式双螺杆压缩机流致噪声分析

Flow⁃induced Noise Analysis for Double Suction Balanced Twin Screw Compressor

双吸平衡式双螺杆压缩机采用对称结构,能够大幅降低机械噪声,从而流致噪声成为主要的噪声。为了研究双吸平衡式双螺杆压缩机内部流体噪声的具体声压级分布,提出利用CFX计算得到双吸平衡式螺杆压缩机的瞬态流场,再将结果进行离散傅里叶变换,运用Actran计算流致噪声。分析计算结果发现:压缩机的噪声频率声压级与压缩机的排气频率及其倍频相关;压力脉动变化率越大声压级越大;转子区域的声压级大于排气区域,排气区域大于进气区域;不同于其他压缩机,双螺杆压缩机的高频声压级仍然较大。

A symmetrical structure is adopted in the double-suction balanced twin-screw compressor, which can greatly reduce the mechanical noise, so that the flow-induced noise becomes the main noise.In order to study the specific sound pressure level distribution of the internal fluid noise of the double-suction balanced twin-screw compressor, the transient flow field of the double-suction balanced screw compressor was calculated by CFX,and the result was subjected to discrete Fourier transform to calculate the flow-induced noise by using Actran.Through analyzing calculation results, it is found that the noise frequency sound pressure level of the compressor is related to the compressor’s exhaust frequency and its multiplication frequency;the greater the pressure pulsation change rate is, the larger the sound pressure level is;the rotor area sound pressure level is greater than that of the exhaust area, the exhaust area sound pressure level is larger than that of the intake area;the high frequency sound pressure level is high, which is different from other twin screw compressors.