The paper presents the main results of the experimental study of acoustic characteristics of the propfan engine with a high-loaded contra-rotating open rotor. The measurements are made during the engine operation under static conditions. The power, directivity, and spectral characteristics of the power plant acoustic field are obtained.

中文翻译：

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静态条件下对开转子转子噪声的研究

本文介绍了高负荷逆向旋转开放式转子螺旋桨发动机声学特性的实验研究的主要结果。这些测量是在发动机在静态条件下运行期间进行的。获得了电厂声场的功率，方向性和频谱特性。