Noise Reduction of a Supersonic Jet Using Gas Injection from a Nozzle Wall
Noise Reduction of a Supersonic Jet Using Gas Injection from a Nozzle Wall
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使用从喷嘴壁喷射气体的超音速射流降噪
DOI：
10.1299/kikaib.71.1798
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
T. Obokata
中科院分区：
文献类型：
--
作者：
Mikiya Araki;K. Kuwabara;Masaaki Arai;T. Ishima;S. Shiga;T. Obokata
实验研究了喷管壁面喷气对超声速欠膨胀射流尖叫抑制的影响。空气从收敛的圆形喷嘴以2.25（M = 1.14）的压力比喷射到大气中（主射流）。主射流喷嘴的出口直径为8.0 mm。空气从安装在主射流喷嘴壁中的小喷嘴沿主射流的法线方向喷射（二次射流）。副喷嘴的出口直径为1.0 mm。副喷嘴的数量选择为2个或4个，并且每个副射流的质量流率设定为主射流的2.0%或4.0%。二次喷流的存在使尖声声压级最大降低了23 dB，同时也影响了宽带噪声的频率分布。在二次射流存在的情况下，随着二次射流总质量流量的增加，主射流的总压力略有下降。结果表明，气体喷射方法在减小尖叫声方面是有效的，且总压损失较小。
Effects of gas injection from a nozzle wall on screech reduction of a supersonic under expanded jet are investigated experimentally. From a converging round nozzle, air is injected into the atmosphere (Main jet) at a pressure ratio of 2.25 (M =1.14). The exit diameter of the main jet nozzle is 8.0 mm. From small nozzles mounted in the main jet nozzle wall, air is injected in the normal direction to the main jet (Secondary jet). The exit diameter of the secondary nozzles is 1.0 mm. The number of the secondary nozzles is selected to be 2 or 4, and the mass flow rate of each secondary jet is set at 2.0% or 4.0% of the main jet. With the secondary jets, the screech SPL is reduced by 23 dB at the maximum, and the frequency profile of the broadband noise is also influenced. And with the secondary jets, the total pressure of the main jet is slightly decreased with the increase in the total mass flow rate of the secondary jets. Consequently, it is shown that the gas injection method is effective in screech reduction with a small loss in the total pressure.