Experimental Study and Simulation of Rocket Engine Freejet Noise
Experimental Study and Simulation of Rocket Engine Freejet Noise
复制标题
火箭发动机自由喷射噪声的实验研究与模拟
DOI：
10.2514/2.1199
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发表时间：
2001
期刊：
影响因子：
2.5
通讯作者：
J. Varnier
中科院分区：
文献类型：
--
作者：
J. Varnier
法国国家环境研究局代表法国国家空间研究中心，在阿丽亚娜5号发射装置升空时的声学环境研究框架内，对美国航天局1970年代的喷流噪声模型进行了近声场模拟。为了验证这一模型，已经用各种尺寸的静态火箭进行了试验。几个改进似乎是必要的声学测量的精确模拟：特别是，模型的特征长度必须减少，必须使用完全扩展的喷气数据，而不是喷气排气数据。结果表明，声学效率，对于一个给定的马赫数，是不依赖于火箭的大小，并可以估计从文献中找到的半经验公式。模型的变化与其他不同特性的射流进行了检查。实验的基础上，并根据推导出的方法从早期的研究，声场的空间特性，更特别的是声功率峰值位置有关的超音速长度的流，这似乎是足够的参考长度为未来的喷气噪声模型。
On behalf of CNES and in the framework of studies concerning the acoustic environment of Ariane 5 launcher at lift-off, ONERA has adapted to the near sound field simulation a NASA's jet noise model of the 1970's. In order to validate this model, tests have been carried out with static rockets of various sizes. Several improvements appear to be necessary for a precise simulation of the acoustic measurements: in particular, the characteristic length of the model must be reduced and the fully expanded jet data must be used instead of the jet exhaust data. It is shown that the acoustic efficiency, for a given Mach number, is not dependent on the rocket size, and may be estimated from a semi-empirical formula found in the literature. The model changes are checked with other jets of various characteristics. On the basis of experiments and following an approach deduced from an earlier study, the spatial characteristics of the sound field and more particularly the sound power peak location are related to the supersonic length of the flow, which appears to be the adequate reference length for a future jet noise model.