{"title":"非周期性诱导的代谢梁稳健设计:数值和实验研究","authors":"","doi":"10.1016/j.ijmecsci.2024.109650","DOIUrl":null,"url":null,"abstract":"<div><p>Various design strategies have been explored to achieve wide local resonance (LR) bandgaps in acoustic metamaterials (AMMs), which have applications in vibration absorption and low-frequency noise mitigation. Conventionally, most methodologies model AMMs as periodic systems. Additionally, maintaining a reasonable resonator mass is desirable for many engineering applications. These factors restrict their possible design space and effectiveness. Such periodic structures are also sensitive to imperfections or manufacturing variabilities. To overcome these issues, we propose a novel methodology for optimal design of robust aperiodic AMMs. First, through a detailed parametric study, we establish a relationship among degree of aperiodicity, bandgap width, and its robustness. A robustness measure is defined to quantify the sensitivity of the bandgap with respect to manufacturing defects. We report two key observations: (i) aperiodicity helps in enhancing the bandgap and robustness, and (ii) the bandgap is not monotonically related to the robustness. These observations suggest the need for a multi-objective optimization in the aperiodic regime. Subsequently, all resonators’ mass, stiffness, and position are treated as design variables in a global optimization problem, which is solved using the genetic algorithm. This methodology offers users complete flexibility in imposing various design constraints.</p><p>Numerically, an AMM beam or metabeam is considered, comprising equally spaced double-cantilever-like resonators on a homogeneous host beam, producing an LR bandgap spanning 750–1000 Hz. Through multi-objective optimization, aperiodic designs with enhanced performance are achieved, with significantly wider and more robust bandgaps than periodic systems with similar mass. Interestingly, the global optima resides in the vicinity of the periodic configuration, as shown by parametric studies. The optimized aperiodic designs are validated through physical experiments on a vibrating beam. These findings open a new avenue for designing metamaterials.</p></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":null,"pages":null},"PeriodicalIF":7.1000,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Aperiodicity induced robust design of metabeams: Numerical and experimental studies\",\"authors\":\"\",\"doi\":\"10.1016/j.ijmecsci.2024.109650\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Various design strategies have been explored to achieve wide local resonance (LR) bandgaps in acoustic metamaterials (AMMs), which have applications in vibration absorption and low-frequency noise mitigation. Conventionally, most methodologies model AMMs as periodic systems. Additionally, maintaining a reasonable resonator mass is desirable for many engineering applications. These factors restrict their possible design space and effectiveness. Such periodic structures are also sensitive to imperfections or manufacturing variabilities. To overcome these issues, we propose a novel methodology for optimal design of robust aperiodic AMMs. First, through a detailed parametric study, we establish a relationship among degree of aperiodicity, bandgap width, and its robustness. A robustness measure is defined to quantify the sensitivity of the bandgap with respect to manufacturing defects. We report two key observations: (i) aperiodicity helps in enhancing the bandgap and robustness, and (ii) the bandgap is not monotonically related to the robustness. These observations suggest the need for a multi-objective optimization in the aperiodic regime. Subsequently, all resonators’ mass, stiffness, and position are treated as design variables in a global optimization problem, which is solved using the genetic algorithm. This methodology offers users complete flexibility in imposing various design constraints.</p><p>Numerically, an AMM beam or metabeam is considered, comprising equally spaced double-cantilever-like resonators on a homogeneous host beam, producing an LR bandgap spanning 750–1000 Hz. Through multi-objective optimization, aperiodic designs with enhanced performance are achieved, with significantly wider and more robust bandgaps than periodic systems with similar mass. Interestingly, the global optima resides in the vicinity of the periodic configuration, as shown by parametric studies. The optimized aperiodic designs are validated through physical experiments on a vibrating beam. These findings open a new avenue for designing metamaterials.</p></div>\",\"PeriodicalId\":56287,\"journal\":{\"name\":\"International Journal of Mechanical Sciences\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":7.1000,\"publicationDate\":\"2024-08-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Mechanical Sciences\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S002074032400691X\",\"RegionNum\":1,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, MECHANICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Mechanical Sciences","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S002074032400691X","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
Aperiodicity induced robust design of metabeams: Numerical and experimental studies
Various design strategies have been explored to achieve wide local resonance (LR) bandgaps in acoustic metamaterials (AMMs), which have applications in vibration absorption and low-frequency noise mitigation. Conventionally, most methodologies model AMMs as periodic systems. Additionally, maintaining a reasonable resonator mass is desirable for many engineering applications. These factors restrict their possible design space and effectiveness. Such periodic structures are also sensitive to imperfections or manufacturing variabilities. To overcome these issues, we propose a novel methodology for optimal design of robust aperiodic AMMs. First, through a detailed parametric study, we establish a relationship among degree of aperiodicity, bandgap width, and its robustness. A robustness measure is defined to quantify the sensitivity of the bandgap with respect to manufacturing defects. We report two key observations: (i) aperiodicity helps in enhancing the bandgap and robustness, and (ii) the bandgap is not monotonically related to the robustness. These observations suggest the need for a multi-objective optimization in the aperiodic regime. Subsequently, all resonators’ mass, stiffness, and position are treated as design variables in a global optimization problem, which is solved using the genetic algorithm. This methodology offers users complete flexibility in imposing various design constraints.
Numerically, an AMM beam or metabeam is considered, comprising equally spaced double-cantilever-like resonators on a homogeneous host beam, producing an LR bandgap spanning 750–1000 Hz. Through multi-objective optimization, aperiodic designs with enhanced performance are achieved, with significantly wider and more robust bandgaps than periodic systems with similar mass. Interestingly, the global optima resides in the vicinity of the periodic configuration, as shown by parametric studies. The optimized aperiodic designs are validated through physical experiments on a vibrating beam. These findings open a new avenue for designing metamaterials.
期刊介绍:
The International Journal of Mechanical Sciences (IJMS) serves as a global platform for the publication and dissemination of original research that contributes to a deeper scientific understanding of the fundamental disciplines within mechanical, civil, and material engineering.
The primary focus of IJMS is to showcase innovative and ground-breaking work that utilizes analytical and computational modeling techniques, such as Finite Element Method (FEM), Boundary Element Method (BEM), and mesh-free methods, among others. These modeling methods are applied to diverse fields including rigid-body mechanics (e.g., dynamics, vibration, stability), structural mechanics, metal forming, advanced materials (e.g., metals, composites, cellular, smart) behavior and applications, impact mechanics, strain localization, and other nonlinear effects (e.g., large deflections, plasticity, fracture).
Additionally, IJMS covers the realms of fluid mechanics (both external and internal flows), tribology, thermodynamics, and materials processing. These subjects collectively form the core of the journal's content.
In summary, IJMS provides a prestigious platform for researchers to present their original contributions, shedding light on analytical and computational modeling methods in various areas of mechanical engineering, as well as exploring the behavior and application of advanced materials, fluid mechanics, thermodynamics, and materials processing.