许自顺，张强，咸凯，胡志睿

(山东大学 能源与动力工程学院，山东 济南 250061)

摘要：发动机排气噪声是工程机械最主要噪声源之一，为达到减小某工程机械用抗性消声器排气噪声目的，根据其结构参数建立了对应几何模型并用hypermesh软件建立了消声器内部声腔的声学三维有限元模型。利用LMS virtual lab 的声学有限元计算模块对消声器进行了声学特性分析并进行了评价，通过改变消声器的结构研究了不同结构参数如孔径、腔体尺寸等对其消声性能的影响，总结出传递损失随结构改动的变化规律。以原消声器的声学性能为参考结合结构参数对其消声性能的影响规律提出提高传递损失的改进方案，按照相关噪声测试标准测量了优化前后的排气噪声，结果表明优化后的排气噪声声压级比优化前降低了1.6dB，证实了优化方案有效性。

关键词：抗性消声器；有限元；声学计算；传递损失；优化

Abstract: Engine exhaust noise is one of the main noise sources of automobile noise.To reduce the exhaust noise of a reactive muffler used on engineering machinery，the geometric model was established according to its structure parameters and also by using hypermesh software three-dimensional acoustic finite element model of the interior acoustic chamber was established. The acoustic characteristics of the muffler were analyzed and evaluated by using acoustic finite element calculation module of software LMS virtual lab，influence of structure change on acoustic characteristics was studied through changing the muffler structural parameters such as the size of the pores and the cavities. Change rules of the transmission loss were summed up along with the change of structures. Taking the former muffler as a reference, a final scheme aim to improve the transmission loss was put forward according to the change rules summed up before. Measurement on exhaust noise before and after the optimization of the muffler was conducted according to the relevant test standard，the result showed that the SPL of exhaust noise after optimization reduced 1.6 dB，which proved the efficiency of the optimization.