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为研究高速气体冲击喷流噪声机理和控制途径,对气流冲击挡板的噪声特性进行了实验研究,并对噪声机理进行理论分析。高速气流喷流不同表面材质挡板的噪声实验表明,挡板表面材质弹性模量越小,气流喷注挡板的噪声越小。弹性模量小的材质容易吸收气体能量,降低作用在挡板上脉动力幅值,进而降低了喷流冲击噪声。喷嘴与挡板之间距离对喷流噪声产生显著的影响,距离增大使得喷流总噪声减小,但低频噪声增大.高速气流冲击挡板时,气流冲击挡板产生的湍动能决定了喷流噪声的大小,改变挡板表面物性是降低喷流噪声的一个重要手段。
In order to study the noise mechanism and control approach of high speed gas impinging jet, the noise characteristics of the impingement baffle were studied experimentally, and the noise mechanism was analyzed theoretically. Experiments on noise of high-speed jet streams with different surface material baffles show that the smaller the elastic modulus of the baffle material, the smaller the noise of the jet nozzle. Materials with low modulus of elasticity easily absorb gas energy and reduce the amplitude of pulsating force acting on the baffle, thus reducing the jet impact noise. The distance between the nozzle and the baffle has a significant impact on the jet noise, the increase of the distance makes the total jet noise decreases, but the low frequency noise increases.When the high-speed air impinges the baffle, the turbulent kinetic energy produced by the impingement damper determines Jet noise size, changing the baffle surface properties is to reduce jet noise is an important means.