Prediction of Combustion Noise in a Model Combustor Using a Network Model and a LNSE Approach
Prediction of Combustion Noise in a Model Combustor Using a Network Model and a LNSE Approach
复制标题
DOI：
10.1115/1.4038026
复制
发表时间：
2017-09
影响因子：
1.5
通讯作者：
Wolfram C. Ullrich;Y. Mahmoudi;Kilian Lackhove;A. Fischer;C. Hirsch;T. Sattelmayer;A. Dowling;N. Swaminathan;A. Sadiki;M. Staufer
中科院分区：
文献类型：
--
作者：
Wolfram C. Ullrich;Y. Mahmoudi;Kilian Lackhove;A. Fischer;C. Hirsch;T. Sattelmayer;A. Dowling;N. Swaminathan;A. Sadiki;M. Staufer
版权所有 © 2018 劳斯莱斯公司。减少现代航空发动机的污染和噪音排放是满足未来空中交通要求的一个关键概念。这需要提高对燃烧噪声及其来源的理解，以及开发准确的预测工具。这是当前研究的主要目标，其中低阶热声网络（LOTAN）求解器和混合计算流体动力学/计算气动声学方法应用于通用预混加压燃烧器，以评估其燃烧噪声预测的能力。 LOTAN 求解线性化欧拉方程 (LEE)，而混合方法由雷诺平均纳维-斯托克斯 (RANS) 平均流和基于线性化纳维-斯托克斯方程 (LNSE) 的频域模拟组成。两个求解器依次输入三个不同的燃烧噪声源项，这些噪声源项是通过在 RANS 模拟上应用统计噪声模型以及不可压缩和可压缩大涡模拟 (LES) 的后处理而获得的。通过这种方式，可以识别源模型和声学求解器的影响。将数值结果与实验数据进行比较。一般来说，LOTAN 和 LNSE 求解器与实验结果吻合良好。就热释放谱的幅度和形状而言，LES 源模型比统计噪声模型提供更好的结果。除此之外，还证明了源项的相位关系不会影响噪声频谱。最后，基于非齐次亥姆霍兹方程的第二次模拟表明空气动力学平均流量对宽带噪声谱的重要性次要。
Copyright © 2018 by Rolls-Royce plc. The reduction of pollution and noise emissions of modern aero engines represents a key concept to meet the requirements of the future air traffic. This requires an improvement in the understanding of combustion noise and its sources, as well as the development of accurate predictive tools. This is the major goal of the current study where the low-order thermo-acoustic network (LOTAN) solver and a hybrid computational fluid dynamics/ computational aeroacoustics approach are applied on a generic premixed and pressurized combustor to evaluate their capabilities for combustion noise predictions. LOTAN solves the linearized Euler equations (LEE) whereas the hybrid approach consists of Reynolds-averaged Navier-Stokes (RANS) mean flow and frequency-domain simulations based on linearized Navier-Stokes equations (LNSE). Both solvers are fed in turn by three different combustion noise source terms which are obtained from the application of a statistical noise model on the RANS simulations and a post-processing of incompressible and compressible large eddy simulations (LES). In this way, the influence of the source model and acoustic solver is identified. The numerical results are compared with experimental data. In general, good agreement with the experiment is found for both the LOTAN and LNSE solvers. The LES source models deliver better results than the statistical noise model with respect to the amplitude and shape of the heat release spectrum. Beyond this, it is demonstrated that the phase relation of the source term does not affect the noise spectrum. Finally, a second simulation based on the inhomogeneous Helmholtz equation indicates the minor importance of the aerodynamic mean flow on the broadband noise spectrum.