Shock-induced noise in supersonic jets

超音速喷气机中的冲击引起的噪声

• 批准号: 5405925
• 负责人: Professor Dr. Jörn Lothar Sesterhenn
• 金额: --
• 依托单位: Centre Acoustique
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2003
• 资助国家: 德国
• 起止时间: 2002-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5405925?language=en
• 关键词: Shock; induced; noise; supersonic; jets

Supersonic jets with complex shock-cell structures produce broadband and smallband noise (screech tones) of high intensity which contributes to structural fatigue and to strong environmental noise pollution. While the screech frequencies are theoretically predictable, their amplitudes cannot, until now, be computed precisely. It is the aim of this project to predict such noise levels reliably and to contribute to a better understanding of the fundamental physics of shock-induced noise generation and propagation. Two different highly accurate compressible Navier-Stokes solvers, available at TU Munich (TUM) and École Centrale de Lyon (ECL) will be used to perforin direct numerical and large-eddy simulations of supersonic perfectly expanded and overexpanded round jets. While the group at ECL will concentrate on LES, the group at TUM will use DNS for flow and noise prediction. One common low Reynolds number flow-case will be defined which allows to compare noise predictions by LES and DNS. Detailed supersonic jet data are the input for noise propagation studies based on the linearized Euler equations. The goal of the project during the next 3-year phase will be related to the control of shockinduced noise by shape modifications of the nozzle lip.

具有复杂激波室结构的超音速射流产生高强度的宽带和小频段噪声（尖叫音），造成结构疲劳和强烈的环境噪声污染。虽然从理论上讲，尖叫声的频率是可以预测的，但到目前为止，它们的振幅还不能精确计算出来。这个项目的目的是可靠地预测这种噪声水平，并有助于更好地理解冲击引起的噪声产生和传播的基本物理。慕尼黑工业大学（TUM）和École里昂中央大学（ECL）将使用两种不同的高精度可压缩Navier-Stokes解算器，对超音速完全膨胀和过膨胀圆形射流进行直接数值模拟和大涡模拟。ECL的团队将专注于LES，而TUM的团队将使用DNS进行流量和噪声预测。将定义一个常见的低雷诺数流情况，以便比较LES和DNS的噪声预测。详细的超音速射流数据是基于线性化欧拉方程的噪声传播研究的输入。该项目未来3年的目标是通过改变喷嘴唇形来控制冲击噪声。