Numerical study on sound absorption characteristics based on virtual impedance tube and dual-channel acoustic sensor

In order to accurately and efficiently study and predict the sound absorption coefficient of acoustic materials, this paper uses the numerical method of virtual impedance tube and dual microphone based on the multi-physics simulation platform to explore related issues. This work establishes a prediction model for the test of material sound absorption characteristics, and numerically models acoustic objects such as impedance tube, dual-channel acoustic sensor, flat porous material composite structure, and wedge-type porous material composite structure. The sound absorption characteristics of two typical forms of composite structures under various conditions such as different thicknesses, different lengths, different back cavity spacings, and different perforation rate panels are studied. The simulation results are compared and evaluated, and the results show that the numerical model can effectively calculate the influence of different states on the sound absorption characteristics of different composite structures. The numerical model can also effectively evaluate the wide-band sound absorption test of the tested samples from 50Hz to 5000Hz by changing the positioning parameters of three groups of virtual impedance tubes with diameters of 30mm, 100mm, and 600mm and dual microphones. This numerical test model can conveniently and quickly evaluate the sound absorption coefficient of the sample material, which can save a lot of sample preparation and selection costs in the early stages of project research.