消声单元产生气流再生噪声的流场分布特征

Fluid Distribution Characteristics of Occurring Flow Regeneration Noise from Muffler Element

采用正交试验设计方法确定了简单扩张腔式消声单元试验样件的具体结构参数,并在自行设计的台架上测量了气流再生噪声,在分析内部流场的基础上提出了流场分布特征参数,建立了气流再生噪声的关系模型.结果表明,当结构参数一定,腔内速度分布特征不随进口气流速度的变化而变化,仅是数值大小的差异,流场冲击特征系数表现出和气流再生噪声变化一致的趋势,与进口气流速度大小无关,获得了气流再生噪声强度和流场冲击特征系数及进口气流速度的关系式,与试验结果吻合较好,为提高消声器的动态消声性能分析提供了重要依据.

Detailed structure parameters of simple expansion chamber muffler element work piece are determined using orthogonal experimental designing method.Flow regenerated noise was measured on the self-design test bench.Based on the analysis of interior flow,the characteristic parameter for fluid field distribution is provided,and related model of flow regenerated noise is established.When structure pa-rameters are constant,velocity distribution characteristic of inner chamber does not vary with the varia-tion of inlet flow velocity,and it only shows the difference in numerical values.Characteristic parameter of flow field distribution shows the same trend to that of regeneration noise.The relationship on flow re-generation noise,the characteristic parameter and inlet velocity is obtained at different velocity.Compari-son shows good agreement between model prediction and experimental data.It provides the reference to improve the dynamic attenuating characteristic of the mufflers.