Jet-noise control via serrated nozzles

航空发动机内部产生的噪声通过旁道和喷嘴传播，并被这些边缘分散。一些现代喷气发动机现在在这些后缘上实现锯齿，试图减少散射噪声。由于没有确定最佳的锯齿，这些设计可能变化很大。该项目将利用分析方法来确定圆柱导管锯齿状尾缘散射的远场噪声，然后使用该解决方案来优化边缘几何形状，以最大限度地降低噪声。将研究硬壁和声学软壁（阻抗）条件。

Noise generated within aero-engines propagates through both the bypass duct and jet nozzle and is scattered by these edges. Some modern jet engines now implement serrations on these trailing edges in an attempt to reduce scattered noise. These designs can vary greatly as no optimal serration has been determined.This project will make use of analytical methods to determine the far-field noise scattered by a serrated trailing edge of a cylindrical duct, then use this solution to optimise the edge geometry for maximum noise reduction. Both hard-wall and acoustically soft-wall (impedance) conditions will be investigated.