• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Noise control of an acoustic cavity coupled with a vibrating plate treated with a spatially varying constrained viscoelastic layer.
【24h】

Noise control of an acoustic cavity coupled with a vibrating plate treated with a spatially varying constrained viscoelastic layer.

机译：声腔与振动板的噪声控制，该振动板经过空间变化的约束粘弹性层处理。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Viscoelastic layers have long been recognized as an effective means of reducing the structural vibrations that can generate undesirably high pressure levels in a coupled acoustic cavity. Constraining the viscoelastic layer increases the effectiveness of the viscoelastic layer by adding transverse shear as a dissipation mechanism in the system. It is proposed in this dissertation to replace the traditionally homogeneous core of a constrained damping layer treatment by a non-homogeneous viscoelastic material in order to further improve the effectiveness of the treatment.;A finite element model is developed to simulate the vibrations of plates treated with a non-homogeneous constrained layer treatment using Reissner-Mindlin plate theory. The predictions of the model are validated against the predictions of a commercially available finite element package (NASTRAN). The model of the plate/constraining layer treatment is then coupled with a finite element model of a coupled acoustic cavity. The integrated model is exercised to consider different material combinations and geometric layouts of the non-homogeneous damping treatment in order to determine general guidelines for producing the largest reduction in sound pressure levels inside an acoustic cavity that is being driven by a flexible boundary.;The predictions of the integrated finite element model are validated through experimental and numerical work. Close agreements are found between theoretical predictions and experimental results. Generally, it is found that damping treatments with stiffer outer perimeters and softer cores are more effective in attenuating the sound pressure levels in the acoustic cavity than other configurations of the non-homogeneous treatment. The theoretical and experimental techniques developed in this dissertation present invaluable tools for the design and performance predictions of plates treated with spatially varying damping treatments and coupled with acoustic cavities. These tools can be extended to include more complex structural/cavity systems such as automobile, aircraft, and helicopter cabins as well as ship interior spaces.
机译：长期以来，粘弹性层被认为是减少结构振动的有效手段，该结构振动会在耦合声腔中产生不希望的高压水平。约束粘弹性层通过在系统中添加横向剪切作为耗散机制来提高粘弹性层的有效性。本文提出用非均质粘弹性材料代替约束阻尼层处理的传统均质芯，以进一步提高处理效果。;建立了有限元模型，模拟了处理过的板的振动。使用Reissner-Mindlin板理论进行非均匀约束层处理。对照市售的有限元软件包（NASTRAN）的预测对模型的预测进行了验证。板/约束层处理的模型然后与耦合声腔的有限元模型耦合。运用集成模型来考虑非均匀阻尼处理的不同材料组合和几何布局，以便确定在弹性边界驱动的声腔内产生最大声压级降低的一般准则。通过实验和数值工作验证了集成有限元模型的预测结果。在理论预测和实验结果之间发现了紧密的一致性。通常，发现与非均质处理的其他配置相比，具有较硬的外周边和较软的芯的阻尼处理在衰减声腔中的声压级方面更有效。本论文开发的理论和实验技术为用空间变化阻尼处理和声腔耦合处理的板的设计和性能预测提供了宝贵的工具。这些工具可以扩展到包括更复杂的结构/空腔系统，例如汽车，飞机和直升机机舱以及船舶内部空间。

著录项

  • 作者

    Leibolt, Mary F.;

  • 作者单位

    University of Maryland, College Park.;

  • 授予单位 University of Maryland, College Park.;
  • 学科 Engineering Mechanical.
  • 学位 Ph.D.
  • 年度 2009
  • 页码 146 p.
  • 总页数 146
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号