A fractal study of sound propagation characteristics in roughened porous materials

被引：11

作者：

Ning, J. F. ^{[1
]}

Zhao, G. P. ^{[1
]}

机构：

[1] Xi An Jiao Tong Univ, Sch Aerosp, State Key Lab Strength & Vibrat Mech Struct, Xian 710049, Peoples R China

来源：

WAVE MOTION | 2017年 / 68卷

基金：

中国国家自然科学基金;

关键词：

Fractal; Surface modification; Roughened porous materials; Sound absorption behavior; PRESSURE-DROP; ABSORPTION BEHAVIOR; SURFACE-TOPOGRAPHY; LAMINAR-FLOW; CELL-WALLS; CONDUCTIVITY; ROUGHNESS; CONTACT; MODELS; WAVES;

D O I：

10.1016/j.wavemoti.2016.09.013

中图分类号：

O42 [声学];

学科分类号：

070206 ; 082403 ;

摘要：

The influence of rough elements of porous materials on sound propagation characteristics in roughened porous materials is investigated. Rough surface topography on the roughened porous materials is simulated by the fractal geometry theory, in which relative roughness is defined clearly as a function of the fractal dimension, porosity, average diameter and diameter ratio of the hexagonal elements on pore wall of the porous materials. Based on the sound propagation model of the smooth porous materials, a sound propagation model of the roughened porous materials is built. The effective density and bulk modulus, acoustic impedance and propagation constant, flow resistivity and sound absorption coefficient of the roughened porous materials are derived and discussed as a function of the relative roughness. It is demonstrated that the sound absorption coefficient of the roughened porous materials is improved as the relative roughness increases. The model predictions for the sound absorption coefficient of the roughened porous materials are well agreed with that of the existing test results. (C) 2016 Elsevier B.V. All rights reserved.

引用

页码：190 / 201

页数：12

共 37 条

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