项目名称: 具有低频宽禁带特性的广义声子晶体新机理研究
项目编号: No.51275377
项目类型: 面上项目
立项/批准年度: 2013
项目学科: 机械、仪表工业
项目作者: 陈天宁
作者单位: 西安交通大学
项目金额: 80万元
中文摘要: 声子晶体为现代声学技术带来新的挑战,其声学禁带机理和低频禁带结构一直是该研究领域的前沿课题之一。本项目以设计具有低频宽禁带特征的声子晶体结构为目标,以含有缝隙结构的声子散射体为对象,从声能量角度出发,引入流体可视化技术,在布拉格散射和局域共振理论基础上,探讨新的理论方法,采用有限元仿真与实验测试相结合的研究手段,探索实现声子晶体内部能量传播、分布和衰减规律可视化的途径,以期获得缝隙结构声子散射体产生声学禁带的本质机理;在此基础上,研究广义条件下缝隙结构特征参数对声能的频率调制机理,建立禁带特性随缝隙特征参数变化的解析模型,并根据解析模型优化缝隙结构参数,获得最低频率和最宽频带相对应的缝隙参数组合;最后,设计多种实验方案,验证理论计算结果。本项目不仅在理论上具有重要的学术价值,在内容和方法上也具有一定的创新性,研究成果将为声子晶体在大型装备隔声降噪以及舰艇声隐身等领域的工程应用提供理论基础。
中文关键词: 声子晶体;缝隙结构;禁带;可视化;优化
英文摘要: Phononic crystal has brought new challenges for the modern acoustic technology, the acoustic band gap mechanism and low-frequency band gap structure has been one of the important subjects of the research areas. The project's goal is to design a new phononic crystal structure with low-bandwidth characteristics of band gap, and the object of study is the phonon inclusions with the gap structure. A new theory on the basis of the Bragg scattering and local resonance theory will be explored, starting from a sound viewpoint of energy and the introduction of flow visualization techniques. In order to obtain the acoustic mechanism of the band gap due to the gap structure of phonon inclusions, the project uses the finite element simulation and experimental tests to study the visual way of illustrating the internal energy propagation, distribution and attenuation law. Then, the gap structure characteristic parameters of the sound energy frequency modulation mechanism in the broad conditions will be studied, and the analytical model of the band gap characteristics varying with the gap characteristic parameters will be established. According to the optimization of the gap structure parameters, the combination of parameters corresponding with the minimum frequency and wide band gap will be obtained. At last some experiments
英文关键词: phononic crystal;gap structure;band gap;visualization;optimization