The implementation of advanced low-emission aircraft engine technologies and the reduction of noise from airframe, fan, and jet exhaust have made noise contributions from an engine core increasingly important. Therefore, meeting future ambitious noise-reduction goals requires the consideration of engine-core noise. This article reviews progress on the fundamental understanding, experimental analysis, and modeling of engine-core noise; addresses limitations of current techniques; and identifies opportunities for future research. After identifying core-noise contributions from the combustor, turbomachinery, nozzles, and jet exhaust, they are examined in detail. Contributions from direct combustion noise, originating from unsteady combustion, and indirect combustion noise, resulting from the interaction of flow-field perturbations with mean-flow variations in turbine stages and nozzles, are analyzed. A new indirect noise-source contribution arising from mixture inhomogeneities is identified by extending the ...

中文翻译：

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燃烧和发动机核心噪音

先进的低排放飞机发动机技术的实施以及机身、风扇和喷气排气噪声的降低，使得发动机核心的噪声贡献变得越来越重要。因此，要实现未来雄心勃勃的降噪目标，就需要考虑发动机核心噪声。本文回顾了发动机核心噪声的基本理解、实验分析和建模方面的进展；解决当前技术的局限性；并确定未来研究的机会。在确定来自燃烧室、涡轮机械、喷嘴和射流排气的核心噪声贡献后，将对它们进行详细检查。来自不稳定燃烧的直接燃烧噪声和间接燃烧噪声的贡献，分析了流场扰动与涡轮级和喷嘴中平均流量变化的相互作用。通过扩展......确定了由混合物不均匀性引起的新的间接噪声源贡献。