Development of acoustic impedance tube system using 3D printing and finite element analysis

This study aims to demonstrate and provide a practical guide on correctly designing, fabricating, and verifying the acoustic impedance tube system. Many parts required to build this tube system were uniquely designed and 3D printed, such as the driver case, specimen holder, microphone holder, etc. In addition, this acoustic tube is designed to meet three functions: standard sound absorption measurement, in-situ measurement, and microphone mismatch measurement. Various types of specimens are tested to verify the accuracy of the measurement and how it compares to the poroelastic theoretical models and FEM models. To estimate the poroelastic parameters, measurement and FEM models were used to run the optimization process. The validation study shows good agreement in all three cases: measurement, the poroelastic model, and the FEM model.