穿孔板噪声谱分析研究

Analysis research on the noise spectrum of perforation plate

水力空化与超声空化是产生空化的两种主要方法,国内外研究者对超声空化的噪声谱研究的非常多.但对于水力空化,一般仅进行应用方面的实验研究,而疏于声学方面的研究.为进一步了解水力空化的声学特性,本文理论上进行板的振动的计算,并用ANSYS模拟穿孔板的振动,研究其振动频率与测得的空化噪声谱之间的联系.研究结果表明,在特定的条件下,测得的噪声谱呈现明显线状谱分布的超声成分,此时高速水流冲击穿孔板引起了穿孔板的强烈振动,发出超声,但在一般情况下,多孔板水力空化噪声谱并不含超声成分,也不具有明显线状谱特性.

The two main methods to cause cavitation are the hydrodynamic cavitation method and the supersonic cavitation method. The noise spectrum caused by supersonic cavitation is widely studied by domestic and foreign researchers. But regarding the hydrodynamic cavitation, only the experimental .study on application is studied generally, and the acoustics research is very limited. To further understand the acoustics characteristic of hydrodynamic cavitation, the theory computation and the ANSYS simulation of the vibration of the perforation plate have been performed to study the relation of the vibration frequency and the cavitation noise spectrum obtained. The conclusion is that under the specific condition, the noise spectrum obtained presents the obvious line spectrum distribution and has ultrasonic ingredient. In that situation, the high-velocity flow impacted perforation plate and caused the perforation plate to vibrate intensely and to send out ultrasonic. But in ordinary circumstances, cavitation noise spectrum caused by perforation plate includes no supersonic ingredient, also does not have the obvious line spectrum characteristic.