Study of establishment of measurement method of acoustic particle velocity and its applications to advanced investigation on acoustical phenomena

为建立声波粒子速度的测量方法，进行了以下研究。然后，进行了应用测量，以证实其对澄清未解决的声学现象的有用性。(A)测试了与声压传声器同时测量的热线式粒子速度传感器的几种校准方法。通过传递函数值或其近似方程进行相对校正是有效的。(B)采用带麦克风的声粒速度传感器进行声阻抗测量。在新泻大学校园的草地和积雪地面上进行了声阻抗测量。其他声阻抗和声传播测量也在北海道非常宽的长草场地上进行。(C)尝试了基于实测声阻抗值计算声传播特性，并且这些结果与实际现场的实测结果相当吻合。(D)采用粒子速度传感器测量声导纳，明确了建筑声学中常见的穿孔板、亥姆霍兹谐振器和缝型结构的声学特性。测量结果清楚地显示了在每个特定频率上的尖峰谐振特性。(E)颗粒速度传感器及其指向性对多孔排水路面的稳健性诊断是有效的。有效地实现了检测仪器的小型化、便携化。(F)利用粒子速度传感器对轻量化双层墙体内插入多孔吸声器“玻璃棉”的声传播进行三维观测，探讨玻璃棉插入高隔声效果的基础。即使在掠入射到壁面的情况下，玻璃棉内的传播方向也必然向法线方向靠拢，从而减弱了重合效应。少

Following studies were carried out to establish measurement methods on acoustic particle velocity. Then, application measurements were tried for the confirming of its usefulness to make unsolved acoustical phenomenon clear(A) Some calibration methods of the hot wire-type particle velocity sensor were tested for simultaneous measurement with sound pressure microphone. Relative correcting method by the transmission function value or by its approximation equation was effective.(B) Applications such as acoustic impedance measurements by use sound particle velocity sensor with microphone were performed. Some acoustic impedance measurements on the field with grass and on the snow-covered ground in the campus of Niigata University were carried out. Other acoustic impedance and sound propagation measurements also carried out on the very wide field with long grass in Hokkaido.(C) Calculations of the sound propagation characteristic based on the measured acoustic impedance values were tried, and … More these results were fairly corresponded to the measured results on the actual field.(D) Acoustic admittance measurements by the particle velocity sensor were applied to make clear for acoustical properties of perforated plate, the Helmholtz resonator and slit-type structure which are well known in architectural acoustics. Measured results clearly showed the resonant characteristics by sharp peak in each specific frequency.(E) The particle velocity sensor and its directivity were effective in the diagnosis for the soundness of porous drain pavement. It was very effective to realize compact potable inspective instruments.(F) The 3-D observation of sound propagation by particle velocity sensor in inserted porous absorber "glass wool" in light weight double wall was tried to investigate the bases of insertion effect of glass wool for the high sound insulation. Even in the case of grazing incidence to the wall, the propagation direction in the glass wool certainly changes to close to normal direction, then it weakened coincident effect. Less