Evaluation of General Performance of Advanced Noise Suppressors including Spherical Reflectors based on the Diagnosis of Aerodynamic Loss and Acoustic Power

基于气动损失和声功率诊断的球面反射器等先进噪声抑制器综合性能评估

基本信息

批准号：
17560211
负责人：
SETO Kunisato
金额：
$ 1.41万
依托单位：
Saga University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

This research has been carried out by the author of this report with the assistance of graduate and undergraduate students as well as a post doctorial student..1. Designing and construction of a vertical wind tunnel: We made a vertical wind tunnel that can generate a vertical jet. Measurement of thrust loss of noise suppressors was easily carried out by using the wind-tunnel. Special attention was paid to the avoidance of pressure drop at the flange of the exit.2. Measurement of thrust: Comparison between thrusts of flows issued from a nozzle with and without a reflector. It was found that the attachment of a reflector reduces a thrust only a little bit. Measurements of thrust loss of perforated tubes were also carried out. The attachment of a perforated tube also reduced the thrust. The amount of the loss, however, decreased as jet pressure ratio increased. Theoretically a perforated tube can increase a thrust at a high pressure ratio.3. Measurement of acoustic power: Change in acoustic power by the attachment of a spherical reflector has measured in a reverberant room in a pressure-ratio-range of 2.0 to 6.0. Measurements of acoustic power of various perforated tubes were also performed.4. Evaluation of General Performance of Advanced Noise Suppressors: Slotted tubes suffered from smaller thrust loss compared to perforated tubes. The performance of noise reduction of slotted tubes was inferior to perorated tubes. From overall view point, a tube with forward slanted perforation with a porosity of 0.03 (practical value) showed best performance among all tested tubes.5. Presentation and publishment :The results of the present research have been presented at 7th ISAIF (Tokyo, 2005), 12th ICSV (Lisbon, 2005), 13th ICSV(2006,Vienna), ASA/AS Joint meeting (Honolulu, 2006), internoise 2006 (Honolulu, 2006) and at another 4 international conference and 19 papers have been published.

这项研究是由本报告的作者在研究生和本科生以及培训后的学生的帮助下进行的..1。垂直风洞的设计和构造：我们制作了一个垂直风洞，可以生成垂直喷气机。通过使用风能轻松实现抑制噪声抑制器的推力损失的测量。特别注意避免出口法兰处的压降2。推力的测量：与反射器和没有反射器的喷嘴发出的流量的推力之间的比较。发现反射器的附件仅减少了一点点的推力。还进行了穿孔管的推力损失的测量。穿孔管的附着也减少了推力。然而，随着射流压力比的增加，损失的量减少。从理论上讲，穿孔的管可以在高压比下增加推力3。声音能力的测量：通过球形反射器的附着来改变声学能力的变化，在压力收视率范围为2.0至6.0的混响室中测量了声音。还进行了各种穿孔管的声力的测量。4。评估高级噪声抑制剂的一般性能：与穿孔管相比，开槽的管损失较小。开槽管的降噪作用低于渗透管。从总体观点点来看，孔隙率为0.03（实用值）的倾斜倾斜穿孔的管显示在所有测试的管中的性能最佳。5。介绍和出版：本研究的结果已于以赛夫（Tokyo，2005年）第7章，第12届ICSV（里斯本，2005年），第13 ICSV（2006年，维也纳），ASA/AS联合会议（Honolulu，2006年），Internoise，Internoise 2006（2006年）（Honolulu，2006年）（Honolulu，2006年），并在另一项国际会议上发布了19页的PAPERSERED。