A Modal Analysis On The Perforation Panel Structure And The Perforation Panel Structure Of Equilateral Triangular Prism By The Finite Element Method

This article attempts to use the computer simulation by finite element method to study the modal frequency of the perforation plate and equilateral triangular prism perforation plate structure, and do a comparison of the two between the modal distribution and frequency changes with the order under the same parameters.First, this article which bases on the finite element theory and sound wave equation , sees wall perforation plate and spatial sound absorbent as the research objects, analyses the modal of the perforation plate and equilateral triangular prism perforation plate by using the large FEM software ANSYS. Besides, it also elaborately describes the changing rules between the perforation plate and equilateral triangular prism perforation plate modal frequency and the perforation plate thickness, diameter of perforation, perforation rate and materials, as well as the modal distribution situation of the two.Secondly, this article takes the perforation plate and equilateral triangular prism perforation plate structure as an example, according to the perforation plate thickness, diameter of perforation, perforation rate and materials compares the changing rules of the modal distribution and frequency changes with the order, and due to the cavity variations of the two, it results in these specific conclusions: (1) when changes any one of the parameters, their frequency both has changed, but it hasn't affected the modal distribution much. (2) when the parameter changes, their frequency and order relation changing rules are basically the same, the perforation plate frequency ascends as a oblique line with the order's increasing, however the equilateral triangular prism absorbing body ascends as a stepped-- type. (3) when any one of the parameters changes, the equilateral triangular prism perforation plate frequency first bigger than the perforation plate frequency and then smaller. (4) in different cavity variations, the extent to which the four parameters affect the frequency of perforation plate and equilateral triangular prism perforation plate structure is: when the order reaches 50th, the materials affect the frequency variation amplitude the most, and then is the effects of the perforation rate and thickness, the smallest one is the effects of the diameter of perforation.The results of this study can offer some perforation plate and acoustic absorbing body design reference materials for the acoustic engineers and architects.