论文部分内容阅读
一、引言声场条件指空气中声波传播的声学条件。当边界影响可以忽略不计时,其声学条件称为自由声场条件。在自由声场条件下进行噪声的测量,能获得比较精确的噪声数据。而在实际噪声测量中,由于反射声的影响,不能满足自由声场条件,使得声压级值与自由声场条件下的结果有一定的偏差。在风机现场噪声测量中,提出了对反射声影响进行修正的问题。本文通过对声场条件的理论分析,得出了反射声修正值的计算公式,指出了声场条件的鉴定方法,并给出了反射声修正值图表。本文的结果不仅适用于风机现场噪声测量,也可用于其它机械现场噪声声压级的测量。
First, the introduction of sound field conditions refers to the acoustic conditions of airborne sound waves. When the boundary effect is negligible, the acoustic condition is called the free acoustic field condition. Measurement of noise in a free acoustic field yields more accurate noise data. However, in the actual noise measurement, the condition of free acoustic field can not be satisfied due to the influence of the reflected sound, which makes the sound pressure level value deviate from the result under the condition of free acoustic field. In the field noise measurement of the wind turbine, the problem of correcting the influence of the reflected sound is proposed. In this paper, through the theoretical analysis of the sound field conditions, the formula of the correction value of the reflected sound is obtained, the method of identifying the sound field condition is pointed out, and the chart of the correction value of the reflected sound is given. The result of this paper is not only suitable for measuring the noise of wind turbines but also for measuring the sound pressure level of other mechanical noise.