基于波束形成和波叠加法的复合声全息技术

近场声全息是一种准确的噪声源识别技术。然而,由于存在测量要求严格、测点数多等缺点,一定程度上限制了它在工业现场的广泛应用。基于此,提出一种基于波束形成和波叠加法的复合声全息技术。首先利用传声器阵列获取声压场信息;再通过波束形成对声源进行定位;然后在这些声源位置附近配置等效源;最后应用波叠加法进行声场重构。该技术的优点是只需要少量传声器,在中、远距离测量,可以方便快速地实现声场重构。采用两个脉动球的声源模型进行了数值仿真,并在半消声室内采用音箱模拟噪声源进行了实验,都准确地重构了模型的外部声场。这表明,该技术可以准确地对辐射体进行声场重构,为其在工业现场中的应用奠定了基础。

A hybrid acoustic holography technique based on beamforming and wave superposition algorithm

Near-field Acoustic Holography (NAH) is an accurate noise source identification technique. However, it processes the disadvantages of the strictness of measurement requirements and needing of a large number of microphones, which restricts its widely applications in industry situations to some extent. A hybrid acoustic holography technique based on beamforming and the wave superposition algorithm was presented, which overcame the above disadvantages of NAH. At first, a microphone array was used to acquire the sound pressure field radiated from a vibrator; then a beamforming algorithm was adopted to localize sound sources; after that, a serial of equivalent sound sources were collocated around these sound sources; at last, the wave superposition algorithm was applied to reconstruct the sound field. It processes the advantages of needing of a small quantity of microphones, a mid-long measurement distance, easiness and efficiency of sound field reconstruction. Numerical simulations were performed based on a two-pulse-ball model; and also experiments were carried out in a semi-anechoic chamber by using two sound boxes to simulate the sound sources. Both of numerical simulations and experimental results had accurately reconstructed the exterior sound field of the models. It was showed that this hybrid technique can exactly reconstruct the exterior sound field of radiators, which will make a base to its applications in industry situations.