Acoustic Modeling of Honeycomb Structures for First Load Direction with Damping Consideration

Abstract

Low-frequency noise control in buildings is a critical issue because of the weak sound insulation in low frequencies (<200 Hz) for doors and partitions. In the present study, an analytical model has been proposed to specify the relationship between the acoustic parameters, such as acoustic impedance, of honeycomb, and the honeycomb geometry has been investigated to vary the resonance frequency of the honeycomb structures and increase the amount of sound absorption coefficient. In this regard, three materials (polycarbonate, polypropylene, and polyurethane), seven angels (45°, 30°, 15°, 0°, −15°, −30°, −45°), and two cell arrangement (1 × 3 and 2 × 6 state) were considered to discern the effect of these parameters on the sound absorption coefficient. Sound absorption in the frequency range of 1 to 500 Hz for angles of 45°, 30°, 15°, 0°, −15°, −30°, and −45° were demonstrated using MATLAB software. A comparison of the results shows that the greatest absolute value of the angle is caused by the highest sound absorption coefficient. By comparing the absorption coefficient values of all three materials, it can be concluded that the 1 × 3 state has higher absorption than the 2 × 6 state; also, the number of resonance peaks of polyurethane material for all angles is greater than the other two materials in the same frequency range. Then, in the first loading type orientation, for having more sound absorption, the panel with the honeycomb core of polyurethane and 1 × 3 state is recommended for cells with an internal angle of −45° in the case study of the present research.