Noise Prediction for a Turbulent Jet

它提出了一种混合概念，该概念被理解为基于对流场的大涡模拟和对声场的计算气动声学方法。该方法被用来模拟喷气噪声，即由湍流喷流产生的气动噪声，因为它是现代民用飞机的主要关注点。斯特拉斯堡大学进行了大涡模拟，需要通过源项激励亚琛大学求解的声学微扰方程。本文主要研究了三维过渡射流和三维全湍流射流的计算。对于这两个问题，都进行了详细的实验研究，以便有一个很好的验证数据库。本项目的目的是开发一种可靠、高效的数值方法，以了解噪声产生的机理，并定位湍流射流流场中的噪声源。最终的概念是朝着未来喷气发动机开发的数字设计到低噪音系统迈出了第一步。

It it proposed to develop a hybrid concept, which is understood to be based on large-eddy simulations for the flow field and computational aeroacoustics methods for the acoustical field. The method is used to simulate jet noise, i.e., aerodynamic sound generated by a turbulent jet, since it is of major concern for modern civilian aircraft. The University of Strasbourg performs the large-eddy simulations, which are required to excite via source terms the acoustic perturbation equations that are solved by the University of Aachen. The study focuses on the computation of a three-dimensional transitional jet and a three-dimensional fully turbulent jet. For both problems detailed experimental studies have been conducted such that an excellent validation database is available. It is the purpose of this project to develop a reliable and efficient numerical method to unterstand the mechanism of noise generation and to locate noise sources in the flow field of turbulent jets. The final concept is meant to be a first step towards a numerical design-to-low-noise system for the development of future jet engines.