EAGER: Tuning Granular Phononic Crystals through Pattern Transformations

EAGER：通过模式变换调整粒状声子晶体

• 批准号: 1649111
• 负责人: Jongmin Shim
• 金额: $ 15万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1649111&HistoricalAwards=false
• 关键词: EAGER; Tuning; Granular; Phononic; Crystals

This EArly-concept Grant for Exploratory Research (EAGER) award supports fundamental research to provide knowledge for a pattern-transformable granular phononic crystal, which may have tunable low-frequency band-gaps. Phononic band-gap materials are composite materials characterized by phononic band-gaps, i.e., frequency ranges in which the propagation of mechanical waves is prohibited. Phononic band-gap materials made of conventional structural materials possess typically fixed narrow phononic band-gaps in some high-frequency ranges. However, unwanted vibrations and noises disturbing human body are characterized by broadband frequency contents in rather low-frequency ranges. Thus, due to this knowledge gap, their practical products has not appeared yet. This new research will open the possibility of practical phononic band-gap materials. Therefore, if this project succeeds, results from this research will benefit the U.S. manufacturing industry. Furthermore, the PI will design hands-on activities relating to pattern transformations for diverse audiences including under-represented minorities and female students. With these activities, the goal is to stimulate students to pursue a career in engineering.The objective of this project is to explore the proof-of-concept of a pattern-transformable two-dimensional granular crystals, which is characterized by its low-frequency tunable phononic band-gaps. The objective is based on the central hypothesis that instability is closely relating to the pattern-transformation-induced bandgap tunability. The hypothesis will be demonstrated by performing the following specific tasks: (1) identification of pattern transform mechanism, (2) experimental validation of the identified mechanism, (3) numerical phononic dispersion relations, and (4) experimental validation of the numerical phononic dispersion relations. The research attempts to take a transformative approach that links conventional instability theory to an uncharted area of granular phononic crystals. Instability phenomenon is nearly length-scale independent. Therefore, the successful completion of this research could have a significant impact in the field of phononic band-gap materials, because the instability-induced mechanism can be adopted for the design of tunable granular phononic crystals using various actuations in a wide range of length scales.

这项探索性研究（急切）奖的早期概念赠款支持基础研究，以提供可转换的可转换的粒状语音晶体的知识，这可能具有可调的低频带隙。语音带隙材料的复合材料为特征在于语音带隙，即禁止机械波传播的频率范围。由常规结构材料制成的语音带隙材料通常在某些高频范围内具有固定的狭窄语音带隙。然而，不良振动和噪音干扰人体的特征是宽带频率内容在相当低频的范围内。因此，由于这种知识差距，他们的实用产品尚未出现。这项新的研究将开放实用的语音带隙材料的可能性。因此，如果该项目成功，则该研究的结果将使美国制造业受益。此外，PI将设计有关不同受众的模式转型的动手活动，包括代表性不足的少数群体和女学生。通过这些活动，目标是刺激学生从事工程职业。该项目的目的是探索对模式转换的二维粒状晶体的概念证明，该晶体的特征是其低频可调的语音带束。目的是基于中心假设，即不稳定性与模式转化诱导的带隙可调性密切相关。该假设将通过执行以下特定任务来证明：（1）识别模式变换机制，（2）对已识别机制的实验验证，（3）数值语音分散关系，以及（4）数值语音分散关系的实验验证。该研究试图采用一种变革性的方法，将常规不稳定性理论与颗粒状音调晶体的未知区域联系起来。不稳定性现象几乎是独立的。因此，这项研究的成功完成可能会对语音带隙材料的领域产生重大影响，因为可以使用各种长度尺度的各种作用来设计可调的颗粒语音晶体的不稳定性诱导的机制。