摘要
水筒是研究水动力噪声的主要设备之一,但由于测量方法的不完善,大大限制了水动力噪声测量结果的可信度。本文比较了现在常用的几种水筒噪声测量方法,分析了其存在的缺点,提出了水筒噪声测量的改进方法——混响箱法,即将水筒的实验段包围在一个较大的水箱内,测出箱内均方声压的空间平均值,经箱内声场的严格校准,计算出被测噪声源的辐射声功率或噪声源自由场中等效无指向声源级。
An objective of noise measurement in water tunnel is to obtain equivalent free field levels i. e.,to convert measured pressure in the facility to values that would be expected if the acoustic reflection due to the facility boundaries did not exist and then to predict the full-scale performance of the model or in some other related cases. In this paper, the sound field properties arround the source of several hydrophone arrangements are analyzed. The results indicate that, due to the reflections of the boundaries, sound fileld in limited space, such as duct and chamber, have complicated spatial distribution. The pressures measured by one fixed hydrophone in water tunnel could not be converted to equivalent free field values.An improved reverberant chamber method is proposed to obtain the acoustic power of the source in facility by measuring the spatial averaging power spectrum of pressures in the chamber surrounding the test section of closed jet water tunnel.
出处
《中国造船》
EI
CSCD
北大核心
1992年第3期70-79,共10页
Shipbuilding of China
