MEMSマイクロフォンアレイを用いた車両周りの流れと音の分離手法の開発

抄録

In order to decompose hydrodynamic pressure fluctuations (HPF) and acoustic pressure fluctuations (APF) around the automobiles, a MESM microphone array and internal model for wind tunnel experiments were developed. A small array can be created by using a MEMS microphone. As a result, pressure fluctuation around an automobile can be divided into HPF and APF by performing wavenumber-frequency analysis using the developed MEMS microphone array. On the surface of the vehicle body, the sound pressure level was proportional to the sixth power of the wind velocity, and it was confirmed that a dipole sound was generated. On the other hand, the pressure level of the flow fluctuations was proportional to the fourth power of the velocity. It is revealed that the developed MESM microphone array is an effective tool for decomposing HPF and APF.