A 56CH MEMS microphone array for measuring wall pressure fluctuation field

Yoshitsugu Naka, Atsuki Miyajima

Research output: Contribution to conferencePaper

Abstract

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.

Original languageEnglish
Publication statusPublished - 1 Jan 2019
Event11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019 - Southampton, United Kingdom
Duration: 30 Jul 20192 Aug 2019

Conference

Conference11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019
CountryUnited Kingdom
CitySouthampton
Period30/07/192/08/19

Fingerprint

pressure field
Microphones
MEMS
turbulent boundary layer
Telephone lines
flow structure
Flow structure
Pressure measurement
Power spectrum
turbulent flow
wind tunnel
Turbulent flow
Wind tunnels
measuring
Field programmable gate arrays (FPGA)
Boundary layers
Calibration
calibration

Cite this

Naka, Y., & Miyajima, A. (2019). A 56CH MEMS microphone array for measuring wall pressure fluctuation field. Paper presented at 11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019, Southampton, United Kingdom.
Naka, Yoshitsugu ; Miyajima, Atsuki. / A 56CH MEMS microphone array for measuring wall pressure fluctuation field. Paper presented at 11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019, Southampton, United Kingdom.
@conference{cd2a6ebd26b1468db3ddb46b1a972ad3,
title = "A 56CH MEMS microphone array for measuring wall pressure fluctuation field",
abstract = "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.",
author = "Yoshitsugu Naka and Atsuki Miyajima",
year = "2019",
month = "1",
day = "1",
language = "English",
note = "11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019 ; Conference date: 30-07-2019 Through 02-08-2019",

}

Naka, Y & Miyajima, A 2019, 'A 56CH MEMS microphone array for measuring wall pressure fluctuation field', Paper presented at 11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019, Southampton, United Kingdom, 30/07/19 - 2/08/19.

A 56CH MEMS microphone array for measuring wall pressure fluctuation field. / Naka, Yoshitsugu; Miyajima, Atsuki.

2019. Paper presented at 11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019, Southampton, United Kingdom.

Research output: Contribution to conferencePaper

TY - CONF

T1 - A 56CH MEMS microphone array for measuring wall pressure fluctuation field

AU - Naka, Yoshitsugu

AU - Miyajima, Atsuki

PY - 2019/1/1

Y1 - 2019/1/1

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=85073631607&partnerID=8YFLogxK

M3 - Paper

AN - SCOPUS:85073631607

ER -

Naka Y, Miyajima A. A 56CH MEMS microphone array for measuring wall pressure fluctuation field. 2019. Paper presented at 11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019, Southampton, United Kingdom.