Article
Engineering, Mechanical
Youchuan Zhou, Lin Ye, Yuan Chen
Summary: A novel dual local resonance metamaterial chain is designed and fabricated for wave attenuation and impact mitigation purposes, with an extended bandgap through both local resonance and diatomic resonance mechanisms. The optimized design shows excellent performance in wave attenuation and impact mitigation, with the best transmission rate driven down to 0.2 compared to a design without resonators at 0.48.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Acoustics
Wen-Han Yin, Fei-Fei Sun, Lei Xiao
Summary: The study investigated a beam structure formed by a periodic parallel constrained layer damping (P-PCLD) using Euler and sandwich beam parallel coupling, which can achieve better flexural wave attenuation performances than other structures.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Mechanical
Yingli Li, Xuening Wang, Gengwang Yan
Summary: This paper investigates the bandgap mechanism and characteristics of two complex periodic lattices for vibration attenuation, analyzing the role of spring and mass elements in ensuring the existence of the bandgap. Analytical expressions for critical values of mass, stiffness, and configuration angle of the lattice are obtained, and the effects of parameters on bandgap width are studied. The proposed Models 1 and 2 have bandgaps 64.8% and 75.9% wider than the classical Model T.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Construction & Building Technology
Lei Gao, Chenzhi Cai, Cheuk Ming Mak, Xuhui He, Yunfeng Zou, Dizi Wu
Summary: This study proposes two types of periodic hollow steel trenches that can simultaneously exhibit Bragg band gaps and local resonance band gaps, aiming to attenuate surface waves induced by ambient vibration and seismic vibration. The effectiveness of these trenches in vibration isolation is demonstrated through numerical calculations and analysis.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Physics, Applied
Mattia Cenedese, Edoardo Belloni, Francesco Braghin
Summary: This paper investigates the interactions of two mechanisms of bandgap formation in mono-coupled periodic structures - Bragg scattering and local resonators. Analytical study on longitudinal elastic waves describes in detail the formation of bandgaps. Local resonators are implemented via a non-traditional model for higher frequencies, with design maps and tuning formulas developed for both infinite and finite structures.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Dandan Xu, Yu Guo
Summary: This study numerically investigates the attenuation of stress waves due to local resonance using the finite element method, revealing that significant reduction in stress amplitude occurs when the frequency of incident stress wave is close to the natural frequency of particles in the composite.
Article
Acoustics
Yan-Zhao Liu, Si-Shun Yu, Ze Liu, Gui-Lan Yu
Summary: The bandgap characteristics of periodic structures have great potential in seismic isolation and vibration mitigation. A T-shaped partially embedded periodic pile barrier is designed and studied, and its simulation results and isolation performance are validated through field experiments. The embedded length is found to be the key parameter affecting vibration attenuation, with smaller embedded length resulting in better performance of the barrier.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Editorial Material
Physics, Multidisciplinary
Shao-Feng Xu, Kuo-Chih Chuang
Summary: The study discusses the disappearing high-frequency Bragg bandgaps in periodic locally resonant metamaterials, explaining the phenomenon through mathematical models and exploring the transition behavior between LR and Bragg bandgaps.
Article
Physics, Applied
Yang Feng, Hao-Jiang Zhao, Wei Li, Chuang Xue
Summary: The paper proposes a local resonant (LR) rod composed of tri-wing rhombus ligament (TRL) resonators arranged periodically within a common hollow rod to create a low-frequency flexural vibration bandgap and considers stiffness in the design of the unit cell of a PnC. The dispersion relations, mode of resonances and vibration transfer function are studied using a finite element method. Numerical simulations and sample tests are conducted to verify the low-frequency bandgap. The results show that the hollow rod with TRL resonators can create a low-frequency flexural vibration bandgap and possess high support structure stiffness.
MODERN PHYSICS LETTERS B
(2023)
Article
Mechanics
Feng Liang, Yao Chen, Haijiang Kou, Yu Qian
Summary: In this paper, a new class of motional two-dimensional hybrid Bragg-locally resonant meta-pipe model is developed, and the interaction behaviors of the bandgap in this meta-structure are explored. The results reveal the formation of hybrid Bragg-LR bandgaps in such a motional meta-structure, and the impacts of motional properties on the bandgaps are discussed. This study provides a more in-depth interpretation for the interaction of Bragg and locally resonant bandgaps, which is especially beneficial to vibration and noise reduction in rotors and fluid-transporting devices.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Acoustics
Renan L. Thomes, Jaime A. Mosquera-Sanchez, Carlos De Marqui Jr
Summary: Locally resonant piezoelectric metamaterials offer outstanding vibration attenuation properties by optimizing the distribution of target frequencies along the beam, leading to enhanced vibration attenuation performance and avoiding energy localization. Genetic-algorithm heuristics are used to handle the large number of design variables, resulting in improved vibration attenuation performance for metastructures with periodic distributions of piezoelements.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Mechanics
Xiao-feng Li, Shu-liang Cheng, Hong-yun Yang, Qun Yan, Bin Wang, Ya-jun Xin, Yong-tao Sun, Qian Ding, Hao Yan, Ya-jie Li, Qing-xin Zhao
Summary: In this paper, a new class of multi-ligament derived structures is proposed. The bandgap characteristics and transmission properties of different derived structures are comprehensively analyzed using the finite element method and Bloch's theorem. The structure's bandgap opening and closing mechanism and vibration and noise reduction capability are explained by stress cloud diagrams and vibration modes. A better bandgap is obtained through structural optimization and active frequency modulation. The propagation characteristics of elastic waves in different derived structures are investigated separately. The results show that the multi-ligament derived structure has excellent bandgap performance and can achieve better vibration and noise reduction capability, greatly improving its engineering practicality. The comprehensive analysis of wave propagation in this paper provides a theoretical basis and technical means for the improvement and design of metamaterials.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Chemistry, Physical
Yu-Chi Su, Sheng-Shiang Wang
Summary: Seismic metamaterials offer an innovative approach to earthquake engineering by reducing the impact of seismic waves without modifying existing structures. This study proposes two novel designs, V- and N-shaped, to achieve a broad bandgap at low frequencies. By adding a line to the letter V, the bandgap can be broadened in the N-shaped design. These designs, arranged in a gradient pattern, combine the bandgaps of metamaterials with different heights. The use of concrete as the base material makes the proposed seismic metamaterial cost-effective. Finite element transient analysis and band structures confirm the accuracy of the numerical simulations, showing effective attenuation of surface waves across a wide range of low frequencies using the gradient V- and N-shaped seismic metamaterials.
Article
Chemistry, Multidisciplinary
Jingru Li, Sheng Li, Zhongjian Miao
Summary: This paper investigates the complex band diagram of flexural waves in a phononic plate with semi-infinite heavy fluid loading. The results show that external fluid loading can adjust the position, bandwidth, and decay level of the band gaps.
APPLIED SCIENCES-BASEL
(2022)
Article
Materials Science, Multidisciplinary
Yongtao Bai, Xiaolei Li, Xuhong Zhou, Peng Li, Michael Beer
Summary: The low-frequency wide-bandgap characteristics of seismic metamaterials can effectively suppress vibration propagation and reduce the risk of extreme loadings like earthquakes. However, the high cost of seismic metamaterials made of general engineering materials due to the stringent requirement of lattice size has been a challenge. In this study, we propose a soil-expanded seismic metamaterial that overcomes the scale restriction and achieves desired bandgap characteristics through the transfer matrix method and finite difference method. Our findings demonstrate that the seismic metamaterial with rubber components can significantly suppress acceleration amplitudes by 90% in the wave propagation region, thereby reducing seismic risk in targeted areas, as confirmed by the response spectra.
MECHANICS OF MATERIALS
(2023)
Article
Acoustics
Sandip Chajjed, Mohammad Khalil, Dominique Poirel, Chris Pettit, Abhijit Sarkar
Summary: This paper reports the generalization of the Bayesian formulation of the flutter margin method, which improves the predictive performance by incorporating the joint prior of aeroelastic modal parameters. The improved algorithm reduces uncertainties in predicting flutter speed and can cut cost by reducing the number of flight tests.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Pascal Zeise, Bernhard Schweizer
Summary: Air ring bearings are an improved version of classical air bearings, providing better damping behavior and allowing operation above the linear threshold speed of instability. However, there is a risk of dangerous vibrations in certain rotor systems, which can be addressed by considering ring tilting effects.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Zbynek Sika, Jan Krivosej, Tomas Vyhlidal
Summary: This paper presents a novel design of a compact six degrees of freedom active vibration absorber with six identical eigenfrequencies. The objective is to completely suppress the vibration of a machine structure with six motion components. By utilizing a Stewart platform structure equipped with six active legs, a spatial unifrequency absorber with six identical eigenfrequencies is achieved. The design is optimized using a correction feedback and active delayed resonator feedback.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Kai Li, Yufeng Liu, Yuntong Dai, Yong Yu
Summary: This paper presents a novel light-powered self-oscillating liquid crystal elastomer (LCE) bow that can self-oscillate continuously and periodically under steady illumination. The dynamics of the LCE bow are theoretically investigated and numerical calculations predict its motion regimes. The suggested LCE bow offers potential advantages in terms of simple structure, customizable size, flexible regulation, and easy assembly.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Carmelo Rosario Vindigni, Giuseppe Mantegna, Calogero Orlando, Andrea Alaimo
Summary: In this study, a simple adaptive flutter suppression system is designed to increase the operative speed range of a wing-aileron aeroelastic plant. The system achieves almost strictly passivity by using a parallel feed-forward compensator implementation and the controller parameters are optimized using a population decline swarm optimization algorithm. Numerical simulations prove the effectiveness of the proposed simple adaptive flutter suppression architecture in different flight scenarios.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Nicco Ulbricht, Alain Boldini, Peng Zhang, Maurizio Porfiri
Summary: The quantification of fluid-structure interactions in marine structures is crucial for their design and optimization. In this study, an analytical solution for the free vibration of a bidirectional composite in contact with a fluid is proposed. By imposing continuity conditions and boundary conditions, the coupled fluid-structure problem is solved and applied to sandwich structures in naval construction, offering insights into the effects of water on mode shapes and through-the-thickness profiles of displacement and stress.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Shahram Hadian Jazi, Mostafa Hadian, Keivan Torabi
Summary: Non-uniformity and damage are the main focus in studying vibrations of beam elements. An exact closed-form explicit solution for the transverse displacement of a nonuniform multi-cracked beam is introduced using generalized functions and distributional derivative concepts. By introducing non-dimensional parameters, the motion equation and its closed-form solution are obtained based on four fundamental functions. The impact of crack count, location, intensity, and boundary conditions on natural frequency and mode shape is evaluated through numerical study.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Eugenio Tramacere, Marius Pakstys, Renato Galluzzi, Nicola Amati, Andrea Tonoli, Torbjoern A. Lembke
Summary: This paper proposes the experimental stabilization of electrodynamic maglev systems by means of passive components, providing key technological support for the Hyperloop concept of high-speed and sustainable transportation.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Pengfei Deng, Xing Tan, He Li
Summary: In this paper, the authors improve the surface morphology method and study the bit-rock interaction model between the rock and the PDC bit, taking into account the impact of blade shape and cutter arrangement. They establish a dynamic model for a deep drilling system equipped with an arbitrary shape PDC bit and propose a stability prediction method. The results show that the shape of the blades and arrangement of the cutters on the PDC bit significantly affect the nonlinear vibration of the drilling system.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Salvador Rodriguez-Blanco, Javier Gonzalez-Monge, Carlos Martel
Summary: In modern LPT designs, the simultaneous presence of forced response and flutter in different operation regimes is unavoidable. Recent evidence suggests that the traditional linear superposition method may be overly conservative. This study examines the flutter and forced response interaction in a realistic low pressure turbine rotor and confirms that the actual response is much smaller than that predicted by linear superposition.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Kabilan Baskaran, Nur Syafiqah Jamaluddin, Alper Celik, Djamel Rezgui, Mahdi Azarpeyvand
Summary: This study investigates the impact of the number of blades on the aeroacoustic characteristics and aerodynamic performance of propellers used in urban air mobility vehicles. The results show that different blade numbers exhibit distinct noise levels, providing valuable insights for further research on propeller noise and aerodynamic performance.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Yongbo Peng, Peifang Sun
Summary: This study focuses on the reliability-based design optimization (RBDO) of the tuned mass-damper-inerter (TMDI) system under non-stationary excitations. The performance of the optimized TMDI system is evaluated using probability density evolution analysis. The results demonstrate the technical advantages of TMDI, including high vibration mitigation performance, considerable mass reduction, and less stroke demand.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Guanfu Lin, Zhong-Rong Lu, Jike Liu, Li Wang
Summary: Vision-based measurement is an emerging method that enables full-field measurement with non-contact and high spatial resolution capabilities. This paper presents a single-camera method for measuring out-of-plane vibration of plate structures using motion-parametric homography to capture image variation and displacement response.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Bronislaw Czaplewski, Mateusz Bocian, John H. G. Macdonald
Summary: Despite two decades of study, there is currently no model that can quantitatively explain pedestrian-generated lateral forces. This research proposes a foot placement control law based on empirical data to calibrate and generalize the rigid-leg inverted pendulum model (IPM) for predicting lateral structural stability.
JOURNAL OF SOUND AND VIBRATION
(2024)
Article
Acoustics
Justine Carpentier, Jean-Hugh Thomas, Charles Pezerat
Summary: This paper proposes an improved method for the identification of vibration sources on a car window using the corrected force analysis technique. By redefining inverse methods in polar coordinates, more accurate results can be obtained.
JOURNAL OF SOUND AND VIBRATION
(2024)
