为研究汽车共振式排气消声器气流再生噪声与气流速度和温度的关系,利用大涡模拟(LES)湍流模型与声类比(AA)方法,建立了消声器流场和声场模型,搭建实验台并验证了模型的正确性.在此基础上,分析了流噪声和湍动能.结果表明:在消声器的结构突变处,流体噪声源和湍动能均较大,云图分布具有一致性.消声器气流再生噪声以3000 Hz以下为主,噪声值随着进口流速的增大而增大,随着气流温度的增大而减小,但频谱特性受流速和温度的影响较小.消声器多场耦合下的气流再生噪声研究结果可为消声器设计提供一定参考.%The relationship between the flow regeneration noise(FRN)and the flow velocity as well as the temperature of resonant mufflers are studied. The models of the fluid field and acoustic field of a resonant muffler are established by means of LES-AA method.The test bench is built and the fluid and acoustic models are verified.On this basis,the FRN and turbulent kinetic energy(TKE)of the muffler are calculated.The computation results reveal that both FRN and TKE have very large values in structural mutation of the muffler and the nephogram distributions of the two parameters are in accordance each other. The FRN frequencies are mainly below 3 000 Hz. The sound pressure level increases with the increasing of inlet flow velocity and decreases with the increasing of the air flow temperature.But its spectral characteristic is less influenced by the flow velocity and temperature.The FRN characteristics of multi-field coupling can be used as a reference for the resonant mufflers design.
展开▼
