二元喷管热喷流噪声特性试验研究

本文用露天热喷管试验台产生喷射噪声，在收敛喷管处临界状态，测量了圆锥喷管、不同宽高比的二元喷管进口加旋与不加旋等条件下的喷射噪声，对二元喷管热喷流噪声的空间分布和频谱进行了分析。结果表明，二元喷管与圆锥喷管热喷热流噪声的声谱分布不同，它减小了喷射噪声低频范围的声压级，并且将噪声能量转移到高频范围，为加快噪声传输过程中的衰减建立了良好条件；二元喷管宽高比参数增大和喷管进口加轴向旋流具有抑制噪声辐射的

Investigation of Noise Characteristics of Hot Exhaust from Two Dimensional Nozzles

In the paper were tested the noise of hot exhaust issuing from convergent conic nozzle and two dimensional nozzle installed on an open air set up which can generate high temperature gas. The conic nozzle and two dimensional nozzle have the same exit area with and without inlet swirling vortex, and the two dimensional nozzles have the aspect ratio parameters of 4.0 and 6.0, respectively. The noise characteristics of the two dimensional nozzle at critical state was analyzed based on experimental data. The results show that by the use of the two dimensional nozzle, the frequency of noise was shifted upward, alleviating the deep rumble of the conic jet, and the increase in aspect ratio and the use of axial swirling vortex may play an active role in reduction of jet noise.