Noise-reduction mechanisms in jet engines: chevrons are the answer

该项目旨在开发新的模型来研究人字形对飞机发动机排气的影响，这是起飞时最强的声源之一。由于在机场附近区域持续暴露于高振幅噪声会导致无数健康问题，因此已经寻求新的策略来减轻这种噪声分量。Chevrons可以修改产生噪声的相干结构的动力学，但它们的大多数参数是通过试验和错误来选择的，并且最大化降噪的机制尚不清楚。通过了解潜在的降噪机制，该项目将促进更安静的排气喷嘴的优化设计，改善飞机噪音对当地社区的影响。

This project aims to develop new models to study the influence of chevrons on the exhaust of aircraft engines, which is one of the strongest sound sources during take-off. As constant exposure to high-amplitude noise in areas close to airports leads to a myriad of health problems, new strategies have been sought to mitigate this noise component. Chevrons may modify the dynamics of the noise-generating coherent structures, but most of their parameters are chosen by trial and error, and the mechanism that maximises noise reduction is not clear. By understanding the underlying noise-reduction mechanisms, this project will facilitate the optimal design of quieter exhaust nozzles, ameliorating the effect of aircraft noise on the local community.