旁支管是应用广泛的共振消声结构。应用解析方法推导旁支管共振结构的传递损失和共振频率计算公式,考虑三维修正,给出旁支管共振消声带宽与各种参数的定量关系,定义消声带宽与共振频率的比值为带宽参数,研究带宽参数与传递损失以及旁支管其他参数的变化关系,最终给出旁支管共振消声带宽计算公式。最后,通过三维有限元方法(Finite Element Method,FEM)计算旁支管的消声带宽并与文中公式结果进行比较,结果显示,两种结果吻合良好,验证了计算公式的可靠性和准确性。 Side branch is a widely used resonance muffler structure. Based on the three-dimensional correction, the quantitative relationship between resonance muffling bandwidth and various parameters of the branch pipe was given. The ratio of the muffling bandwidth to the resonance frequency was defined as the bandwidth parameter. The relationship between bandwidth parameters and transmission loss and other parameters of the branch pipe is studied. Finally, the formula for calculation of the resonance muffler bandwidth of the branch pipe is given. Finally, the noise cancellation bandwidth of the branch pipe is calculated by the Finite Element Method (FEM) and compared with the results in the paper. The results show that the two results are in good agreement, which verifies the reliability and accuracy of the calculation formula.