The present study aims to develop a 56ch MEMS microphone array for turbulent wall pressure fluctuation measurement. 56 microphones are controlled by a FPGA, and the microphones are arranged in line to obtain spanwise distributions of the wall pressure fluctuations in a turbulent boundary layer. Output data of the MEMS microphones are converted to the actual pressure fluctuations based on the calibration using a reference microphone. The background noise in the wind-tunnel is reduced by splitting the data into POD modes. The noise-reduced data are reconstructed by excluding the modes containing significant amount of noise. The normalized RMS values of the wall pressure fluctuations are in good agreement with the data in the literature, and the power spectra show smooth curves down to the wall unit frequency. Two-dimensional fluctuating wall pressure field and the two-point correlation of fluctuating wall pressure indicate contributions of the turbulent flow structures. The present method can be extended to build a massively parallel fluctuating pressure measurement system.
|出版物ステータス||Published - 1 1 2019|
|イベント||11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019 - Southampton, United Kingdom|
継続期間: 30 7 2019 → 2 8 2019
|Conference||11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019|
|期間||30/07/19 → 2/08/19|