论文部分内容阅读
实际声强测量时常常存在风流或水流,如在飞机或船舶上进行测量,声强探头将受到湍流边界层脉动压力的影响。如何评估该影响以及如何修正测量结果是人们十分关心的工程实用问题。该文首先简要介绍了建立的由湍流边界层脉动压力诱发声强的理论模型。接着利用现有的湍流边界层脉动压力频率-波数谱模型,对湍流边界层脉动压力及其诱发的声强进行了数值分析。为了验证理论模型及数值结果,设计制作了一套实验装置,对湍流边界层脉动压力及其产生的声强进行了具体测量分析。结果表明,湍流边界层脉动压力的测量结果与数值结果吻合良好,测量得到的边界层脉动压力诱发的声强特性与计算结果也十分一致,但必须注意对测量传感器的空间响应进行修正。
Wind or water flow is often present in actual sound intensity measurements, as measured on an aircraft or ship, and the sound intensity probe will be affected by the pulsating pressure at the turbulent boundary layer. How to assess the impact and how to correct the measurement results is a practical engineering problem that people are very concerned about. In this paper, the theoretical model of the induced sound intensity induced by the fluctuating pressure in the turbulent boundary layer is briefly introduced. Then the existing turbulent boundary layer fluctuating pressure frequency - wave number spectrum model is used to analyze the fluctuating pressure and the induced sound intensity in the turbulent boundary layer. In order to verify the theoretical model and the numerical results, a set of experimental apparatus was designed and produced to measure the turbulent boundary layer pulsation pressure and the intensity of the generated sound. The results show that the measurement results of the fluctuating pressure in the turbulent boundary layer are in good agreement with the numerical results. The sound pressure characteristics induced by the fluctuating pressure in the boundary layer are in good agreement with the calculated results. However, the spatial response of the measuring sensor must be corrected.