Langenais A, Vuillot F, Troyes J, Lambaré H
Office National d'Études et de Recherches Aérospatiales, University of Paris-Saclay, F-91123 Palaiseau, France.
Office National d'Études et de Recherches Aérospatiales, University of Toulouse, F-31055 Toulouse, France.
J Acoust Soc Am. 2021 Mar;149(3):1989. doi: 10.1121/10.0003759.
This study aims to numerically investigate the noise radiated by a reduced-scale rocket engine jet at lift-off conditions including a flame trench. An over-expanded Mach 3.1 hot jet entering a flame duct where it impinges on a deflector before being guided in a horizontal duct is considered. The computation is performed with a two-way coupled approach on unstructured grids. This methodology relies on a large-eddy simulation of the jet and the acoustic near field, associated with a full Euler simulation of the acoustic far field. The aerodynamic and acoustic results are compared to a previous computation involving the Ffowcs Williams and Hawkings approach and show a better agreement with the measurements conducted at the MARTEL facility. A more careful analysis of the pressure field suggests that the noise is strongly influenced by the flame trench geometry. Nonlinear propagation effects, natively taken into account by the full Euler solver, are finally highlighted and discussed. Based on appropriate metrics, a good agreement with the experiment is obtained.
本研究旨在对缩尺火箭发动机在包括火焰槽的起飞条件下产生的喷气噪声进行数值研究。研究考虑了马赫数为3.1的过膨胀热喷气流进入火焰管道，在撞击导流板后被导入水平管道的情况。计算采用非结构化网格上的双向耦合方法进行。该方法依赖于对喷气流和声学近场的大涡模拟以及声学远场的全欧拉模拟。将空气动力学和声学结果与之前使用Ffowcs Williams和Hawkings方法进行的计算进行了比较，结果表明与在MARTEL设施进行的测量结果吻合得更好。对压力场的更仔细分析表明，噪声受到火焰槽几何形状的强烈影响。最后突出并讨论了全欧拉求解器本身考虑的非线性传播效应。基于适当的度量标准，计算结果与实验结果吻合良好。
