Article
Acoustics
Pengcheng Zhao, Kai Zhang, Fang Hong, Zichen Deng
Summary: This study proposes a lattice design strategy that considers chirality and tacticity to achieve a low-frequency band gap, and investigates the design of elastic wave logic gates. The study also analyzes the effects of different structural parameters on dynamic properties with experiments conducted to verify vibration transmission performance.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Environmental Sciences
Kai Hakon Christensen, Jan Erik Hobaek Weber
Summary: This study investigates surface effects on deep-water gravity waves theoretically by applying a Robin boundary condition with a complex Robin parameter. The Robin condition combines shear stress and horizontal velocity at the ocean surface. The results show that this condition can describe wave damping related to surface phenomena such as elastic films or thin viscous fluid layers, and it may also model wave generation induced by oscillating surface stresses depending on the signs and magnitudes of the Robin parameter.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Physics, Applied
Gregory J. Chaplain, Richard Craster, Nick Cole, Alastair P. Hibbins, Timothy A. Starkey
Summary: Research has shown that Scholte modes localized between a submerged axisymmetric structured elastic plate and surrounding fluid can be converted into radiative modes via Umklapp diffraction, with experiments confirming the focusing of underwater sound across a wide range of frequencies. This focusing phenomenon is achieved through structured beams forming a cone at a desired spatial position associated with an abrupt change in the patterning of the plate.
PHYSICAL REVIEW APPLIED
(2021)
Article
Mathematics, Applied
Shengjie Yao, Yijun Chai, Xiongwei Yang, Yueming Li
Summary: Researchers design a twisting metamaterial for longitudinal-torsional (L-T) mode conversion in pipes based on the theory of perfect transmodal Fabry-Perot interference (TFPI). The metamaterial can be conveniently designed in a rectangular coordinate system, allowing for efficient L-T mode conversion in pipes of different radii. Experimental results on an aluminum pipe are in good agreement with numerical calculations, indicating potential applications of the proposed metamaterial and its design methodology in ultrasonic devices.
APPLIED MATHEMATICS AND MECHANICS-ENGLISH EDITION
(2023)
Article
Chemistry, Multidisciplinary
Kobi Cohen, Shai Tsesses, Shimon Dolev, Yael Blechman, Guy Ankonina, Guy Bartal
Summary: Controlling and manipulating surface waves is highly beneficial for imaging applications, nanophotonic device design, and light-matter interactions. In this study, weakly modulated metasurfaces were introduced to unlock important structural degrees of freedom and control wave propagation. By utilizing groove-structuring with varying depths and periodicities, the researchers demonstrated control over the transport of surface waves and discovered a yet unexplored, dual-stage topological transition. These findings provide a simple and versatile approach for controlling wave propagation in artificial media.
Article
Engineering, Mechanical
Zhizhou Zhang, Jeong-Ho Lee, Grace X. Gu
Summary: This study explores the physical origin of electro-momentum coupling by employing a high throughput sweep over the microstructure design space of a piezoelectric composite system, and demonstrates how material constituent properties and geometrical arrangements can affect electro-momentum coupling.
EXTREME MECHANICS LETTERS
(2022)
Article
Geochemistry & Geophysics
Chunquan Yu, Jorge C. Castellanos, Zhongwen Zhan
Summary: Surface wave scattering, caused by lateral heterogeneity, has been observed and modeled for years. By analyzing the converted surface waves, this study successfully mapped strong lateral heterogeneities across the entire contiguous United States. The distribution of scatterers correlates well with known geological features, with different sources of scattering identified in different regions.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Physics, Applied
Di Liu, Pai Peng, Wenjie Yu, Qiujiao Du, Fengming Liu
Summary: In this study, a double-scatterer structure is proposed to achieve complete conversion of elastic bulk waves. Each unit of the elastic metamaterial slab contains a pair of scatterers with a relatively oblique direction. When attached to a semi-infinite solid background, the slab can completely convert the normal incident longitudinal wave into a reflected shear wave, or vice versa. The conversion is attributed to the in-phase coupling of the double scatterers' quadrupolar resonances, resulting in oblique displacements and horizontal displacements for reflected waves.
APPLIED PHYSICS EXPRESS
(2023)
Article
Engineering, Mechanical
Zhu-Long Xu, Dan-Feng Wang, Tomohiro Tachi, Kuo-Chih Chuang
Summary: Wave mode conversion has been studied using a Kresling origami wave-mode converter that transforms longitudinal waves into torsional waves. Experimental verification shows potential applications in wave manipulation and energy distribution.
EXTREME MECHANICS LETTERS
(2022)
Article
Physics, Applied
Yijun Chai, Song Zhang, Xiongwei Yang, Yueming Li
Summary: This study introduces the concept of patch sticking for elastic wave manipulation, specifically for efficient mode conversion between in-plane longitudinal and transverse waves. The carefully designed patches are stuck with specific distances and angles, and the working mechanism is revealed through eigen-frequency analysis and experimental validation.
APPLIED PHYSICS EXPRESS
(2023)
Article
Mechanics
Benjamin K. K. Smeltzer, Olav Romcke, R. Jason Hearst, Simen A. Ellingsen
Summary: When surface waves interact with ambient turbulence, turbulent eddies get redirected, intensified and periodically stretched and compressed, while the waves suffer directional scattering. In this study conducted at the Norwegian University of Science and Technology (NTNU), the mutual interactions between surface waves and turbulence were experimentally studied in a water channel laboratory. The experimental results showed that there was a strong enhancement of streamwise vorticity near the surface, in agreement with theory, and that the directional wave spectrum broadened with increasing propagation distance.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Engineering, Mechanical
Yongdu Ruan, Xu Liang
Summary: The paper proposes a surface impedance matched method for designing reflective elastic metasurfaces and demonstrates their effective control over reflected waves. The results show that the designed metasurface can accurately redirect reflected waves and efficiently suppress scattering waves, potentially enabling functionalities of flexural wave manipulation.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Engineering, Marine
Han Lei, Zhang Mindi, Tan Zhenkun, Huang Guohao, Huang Biao
Summary: The objective of this paper is to investigate the energy conversion process of a single bubble collapse under different boundaries using combined experimental and computational modeling. In the experiments, high-speed photography is used to record the temporal and spatial evolution of a single bubble collapse near free-field, rigid, and elastic boundaries. This paper compares the energy conversion process of near-spherical bubbles near the elastic and rigid boundaries when gamma = 1.4. The results show that boundaries have an inhibitory effect on the conversion of potential energy into kinetic energy, with the eta kin/pot of the elastic boundaries being larger than that of the rigid boundary.
Article
Mechanics
Takahito Iida, Ahmad Zareei, Mohammad-Reza Alam
Summary: The trajectory of surface gravity waves is influenced by gravitational acceleration, water density, and sea bed depth. In order to create an omnidirectional cylindrical cloaking device for finite-depth/deep-water waves, an elastic composite plate floating on the surface is proposed. The physical parameters of the plate are optimized to reduce scattered wave energy and wave drift force exerted on the object.
JOURNAL OF FLUID MECHANICS
(2022)
Review
Chemistry, Multidisciplinary
Atif Saleem, Yuezhou Zhang, Muhammad Usman, Muhammad Haris, Peng Li
Summary: Tailored mesoporous carbon nanostructures (TMCNs) with distinctive and tunable morphologies have attracted significant interest. This review provides an authoritative reference on the synthesis pathways, applications, challenges, and future research directions of TMCNs. The control of reaction parameters and selection of appropriate synthesis methods are crucial in obtaining mesoporous carbon materials with precise architectural designs. These materials have great potential applications in energy storage and conversion, catalysis, adsorption, and biomedicine.
Article
Acoustics
G. J. Chaplain, J. M. De Ponti
Summary: This paper presents the design of a device that converts guided elastic waves into non-axisymmetric flexural waves efficiently. By creating an elastic spiral phase pipe, the generation of non-axisymmetric waves is achieved. The design is verified through numerical simulations and experiments, confirming its effectiveness in solving the energy and information transmission problems.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Nanoscience & Nanotechnology
Salome Sanchez, G. Gaspard, C. J. Hyde, I. A. Ashcroft, G. A. Ravi, A. T. Clare
Summary: Heat treatment is crucial for post additive manufactured products to optimize their metallurgical condition. This study focuses on LPBF alloy 718 and reveals the instability of its microstructure under thermal and thermomechanical exposure conditions. The study emphasizes the importance of appropriate heat treatment in relation to future service conditions, and provides recommendations for achieving an ideal microstructure for improved performance.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Multidisciplinary Sciences
G. J. Chaplain, I. R. Hooper, T. A. Starkey
Summary: We propose and investigate a multi-scale bullseye antenna for broadband manipulation of microwaves. The antenna achieves far-field beam-forming through tailored diffraction at the interface of two concentric bullseye geometries, while near-field energy concentration is achieved through the overlap of diffracted beams.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Correction
Physics, Multidisciplinary
G. J. Chaplain, J. M. De Ponti, R. V. Craster
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
G. J. Chaplain, A. S. Gliozzi, B. Davies, D. Urban, E. Descrovi, F. Bosia, R. V. Craster
Summary: By 3D printing samples from a photo-responsive polymer, we can dynamically fine-tune the operating frequency of a topological waveguide using laser excitation, addressing the potential weakness of fixed narrow band of frequencies. This approach significantly improves upon existing static tunability strategies based on modifying the geometry. We demonstrate our method using a version of the classical Su-Schrieffer-Heeger model.
APPLIED PHYSICS LETTERS
(2023)
Article
Mechanics
Luca Rosafalco, Jacopo Maria De Ponti, Luca Iorio, Raffaele Ardito, Alberto Corigliano
Summary: This paper describes a reinforcement learning approach to design optimised graded metamaterials for mechanical energy confinement and amplification. The reinforcement agent is trained using the proximal policy optimization algorithm to determine the lengths and spacing of a resonator array. The results of the optimization process confirm the effectiveness of the proposed approach and the robustness of graded resonator systems for energy confinement and amplification.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Mathematics, Applied
R. Wiltshaw, J. M. De Ponti, R. Craster
Summary: We develop analytical solutions based on singular Green's functions for efficient simulations of wave propagation through an elastic plate with periodic arrays of elastic beams. Our versatile methodology allows us to solve various problems related to multiple beams per primitive cell over different length scales. We validate our approach through cross-verification with finite element numerical simulations. The accuracy and flexibility of our solutions are demonstrated by engineering topologically non-trivial states and designing topological circuits with robust waveguiding.
QUARTERLY JOURNAL OF MECHANICS AND APPLIED MATHEMATICS
(2023)
Article
Physics, Multidisciplinary
Richard Craster, Sebastien Guenneau, Muamer Kadic, Martin Wegener
Summary: Mechanical metamaterials, designed composites with elastic behaviors and effective mechanical properties beyond those of their individual ingredients, have made significant progress in the last decade due to advances in computational science and manufacturing. This review provides a tutorial on its mathematical basis and summarizes the state-of-the-art in both conceptual and experimental aspects.
REPORTS ON PROGRESS IN PHYSICS
(2023)
Article
Physics, Applied
Jacopo M. De Ponti, Luca Iorio, Gregory J. Chaplain, Alberto Corigliano, Richard V. Craster, Raffaele Ardito
Summary: This article presents the key demand in wave physics and engineering to precisely manipulate the direction and redirection of vibrational wave energy. The authors propose a frame-like material that combines the control of topological edge states with the addition of microresonators. This enables precise vibration control on a macroscopic scale, offering opportunities for robust signal transport and vibration control. Experiments, theory, and simulation are used to provide a comprehensive analysis and interpretation of the physics.
PHYSICAL REVIEW APPLIED
(2023)
Article
Chemistry, Multidisciplinary
Wenqi Li, Paul Dryburgh, Don Pieris, Rikesh Patel, Matt Clark, Richard J. Smith
Summary: This paper presents a method for measuring the microstructure of industrially relevant surface finishes. Spatially resolved acoustic spectroscopy is used to measure the microstructure, and the influence of surface roughness on the measurements is discussed. It is demonstrated that a wide range of surface finishes can be measured, but the correlation length of the roughness has a significant impact on the ability to detect surface waves.
APPLIED SCIENCES-BASEL
(2023)
Article
Multidisciplinary Sciences
Fernando Perez-Cota, Giovanna Martinez-Arellano, Salvatore La Cavera III, William Hardiman, Luke Thornton, Rafael Fuentes-Dominguez, Richard J. Smith, Alan McIntyre, Matt Clark
Summary: There is a strong correlation between the elasticity of cells and tissue and their different states (normal, dysplastic, and cancerous). However, advancements in cell mechanics have not been effectively utilized in clinical applications. This study explores the use of phonon acoustics to measure the elastic properties of cancerous and normal breast cells. Through deep learning techniques and a physical model, the researchers achieved a high accuracy rate in differentiating between different cell lines. The development of a compact sensor design also opens up exciting possibilities for future applications with needles and endoscopes.
SCIENTIFIC REPORTS
(2023)
Article
Mechanics
L. Iorio, J. M. De Ponti, A. Corigliano, R. Ardito
Summary: Elastic metamaterials and phononic crystals are effective ways to create band gaps for elastic or acoustic travelling waves. This study introduces a different metamaterial structure that generates larger band gaps with lower added mass by coupling two contra-propagating modes.
MECHANICS RESEARCH COMMUNICATIONS
(2023)
