均匀流直通穿孔管消声器声学特性预测的有限元法

将有限元法应用于预测有均匀流存在时直通穿孔管消声器的声学特性,推导了考虑运流效应的有限元法计算公式,并给出了声学特性的计算方法和数值实施过程。传递损失数值计算结果表明,随着气流马赫数的增加,消声器中高频的消声量有所增加。为精确预测直通穿孔管消声器的声学特性,流速对消声器内声传播的影响应加以考虑。

Finite Element Method for Prediction of Acoustic Attenuation Characteristics of Straight-Through Perforated Tube Silencer with Steady Air Flow

The finite element method（FEM） is applied to predict acoustic attenuation characteristics of straight-through perforated tube silencer with steady air flow.The finite element formulation is carried out,and the numerical method and procedure for predicting the acoustic attenuation characteristics are introduced.Since the convective effect is taken into consideration,the present method is suitable for the case with steady air flow.Transmission loss of straight-through perforated tube silencer is then predicted using three-dimensional finite element method.The numerical results show that the acoustic attenuation effect is raised in the medium and higher frequency range as the Mach number of the flow is increased.It is suggested that in order to predict the acoustic attenuation characteristics of straight-through perforated tube silencer accurately,the influence of steady flow on the sound propagation in the silencer should be considered.