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: 8171741
• 负责人: WILLIAM AUSTIN O'BRIEN
• 金额: $ 0.11万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8171741
• 关键词: Acoustics; Air; Cochlea; Code; Complex; Computer Retrieval of Information on Scientific Projects Database; Data; Devices; Ear; Elements; Funding; Goals; Grant; Head; 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.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目及 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 空军科学研究办公室 (AFOSR) 有兴趣寻找声能进入人体头部的途径。由于航空母舰飞行甲板上的噪音水平较高，即使佩戴耳塞和耳罩也可能会出现听力损失。这是由于声音通过空气以外的传导路径到达耳蜗。这项研究的目标是找到这些途径，以便开发出减少通过它们的声能的设备。为了验证这些路径，有必要获得整个头部的压力。由于我们有兴趣了解在高强度声音的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，因此不存在封闭形式的解决方案。离散时间有限元方法可以模拟多层的复杂几何形状，因此非常适合近似人体头部的声音散射。一种可用于近似能量传播的方法是声射线追踪。射线追踪使用根据有限元代码计算的压力数据来通过几何体传播射线网格，当几何声学合适时，该几何体应大致对应于几何声学预测的射线路径。然后，我们可以通过沿传播方向穿过横截面的射线密度来近似体积中的能量。通过这种方式，人们可以通过定位穿过其中的高密度射线的路径来确定主要能量路径。