FINITE ELEMENT SIMULATION OF SOUND WAVE PROPAGATION INTO THE HUMAN HEAD

声波传播到人脑的有限元模拟

• 批准号: 7956291
• 负责人: WILLIAM AUSTIN O'BRIEN
• 金额: $ 0.08万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7956291
• 关键词: Acoustics; Air; Biomedical Research; Cochlea; Code; Complex; Computer Retrieval of Information on Scientific Projects Database; Data; Devices; Ear; Elements; Funding; Goals; Grant; Head; High Performance Computing; Human; Institution; Learning; Methods; Pathway interactions; Research; Research Personnel; Resources; Solutions; Source; Time; Travel; United States National Institutes of Health; density; hearing impairment; interest; pressure; simulation; sound

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The Air Force Office of Scientific Research (AFOSR) is interested in finding the pathways through which sound energy travels into the human head. Due to the high sound levels encountered on the flight deck of air craft carriers, it is possible to suffer hearing loss even when wearing ear plugs and ear muffs. This is due to sound reaching the cochlea through conducting pathways other than air. The goal of this research is to find these pathways so that devices may be developed to reduce the acoustic energy traveling through them. In order to verify these paths it is necessary to obtain the pressure throughout the head. Since we are interested in learning the pathways to the ear in situations with high levels of sound, a simulation must be performed. The head is a complex scatterer with multiple layers and complex geometries so a closed form solution doesn't exist. The discrete-time finite element method allows for simulation of complex geometries with multiple layers, and is therefore ideal for approximating sound scattering from the human head. A method that can be used to approximate the propagation of energy is acoustic ray tracing. Ray tracing uses the pressure data computed from the finite element code to propagate a grid of rays through the geometry that should roughly correspond to the ray paths predicted by geometrical acoustics when geometrical acoustics are appropriate. One can then approximate the energy in a volume by the density of rays going through a cross-section in the direction of propagation. In this way, one can determine the dominant energy pathways by locating the paths with a high density of rays passing through it.

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 空军科学研究办公室(AFOSR)感兴趣的是寻找声音能量进入人脑的途径。由于航空器航母的飞行甲板上遇到的声级很高，即使戴上耳塞和耳罩也有可能遭受听力损失。这是由于声音通过空气以外的传导途径到达耳蜗处。这项研究的目标是找到这些路径，以便开发设备来减少通过这些路径的声能。为了验证这些路径，有必要获得整个头部的压力。由于我们有兴趣学习在高音量情况下到达耳朵的路径，因此必须进行模拟。头部是一个复杂的散射体，具有多层和复杂的几何形状，因此不存在闭合形式的解。离散时间有限元方法允许模拟复杂的多层几何形状，因此是近似人头的声音散射的理想方法。一种可以用来近似能量传播的方法是声线追踪。射线追踪使用从有限元程序计算的压力数据来传播通过几何的射线网格，当几何声学适当时，该几何应该大致对应于由几何声学预测的射线路径。然后，人们可以通过光线在传播方向上通过横截面的密度来近似体积中的能量。通过这种方式，人们可以通过定位通过它的高密度射线的路径来确定主要的能量路径。