# Sounding Mechanism of a Flue Organ Pipe—A Multi-Sensor Measurement Approach

## TL;DR

This paper explores how a flue organ pipe produces sound by combining sensor measurements and simulations to study air flow and jet behavior.

## Contribution

The novelty lies in integrating multi-sensor data and numerical simulations to analyze the air flow and excitation mechanisms in a flue organ pipe.

## Key findings

- Measurements using a 3D acoustic vector sensor and high-speed camera reveal detailed jet behavior and sound excitation.
- Numerical simulations with ParaVIEW align with experimental data, offering insights into the pipe's sound production.
- The study suggests potential for machine learning to enhance future investigations of pipe organ acoustics.

## Abstract

This work presents an approach that integrates the results of measuring, analyzing, and modeling air flow phenomena driven by pressurized air in a flue organ pipe. The investigation concerns a Bourdon organ pipe. Measurements are performed in an anechoic chamber using the Cartesian robot equipped with a 3D acoustic vector sensor (AVS) that acquires both acoustic pressure and air particle velocity. Also, a high-speed camera is employed to observe the jet coming out from the windway. For that purpose, the steam resulting from dry ice and hot water is used. A numerical simulation of the sounding mechanism of a pipe of the same geometry is based on measuring the pressure signal and the intensity field around the mouth employing an intensity probe and visualizing and observing the motion of the air jet, which represents the excitation mechanism of the system. The ParaVIEW software serves for the simulation and visualization of the air jet. Then, the results obtained from measurements and simulations are compared and discussed. Also, some future directions discussing the application of a machine-learning approach to the area of pipe organ air flow investigation are contained in the Conclusions section.