Article
Engineering, Mechanical
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: This study aims to provide a semi-analytical model for wave propagation in fractionally damped nonlinear phononic crystals, emphasizing the importance of considering nonlinearities in modeling periodic materials and providing new insight into energy dissipation in phononic crystals.
NONLINEAR DYNAMICS
(2022)
Article
Physics, Multidisciplinary
Soroush Sepehri, Mahdi Bodaghi
Summary: This paper investigates the influence of Coulomb damping on the wave propagation behavior of cubically nonlinear monoatomic phononic chains. The nonlinear dispersion relation is obtained analytically using the multiple scales method and the band structure of the damped nonlinear chains is compared to the linear and nonlinear undamped chains. Coulomb damping can lead to lower dispersion frequencies in the chain due to the coupling between the amplitude and the frequency, resulting from the nonlinear nature of the chain. This study captures the effect of Coulomb damping on the wave propagation behavior of nonlinear lattices, bringing us closer to developing a comprehensive analytical model for the behavior of damped phononic crystals.
Article
Physics, Applied
Yeongtae Jang, Geon Lee, Eunho Kim, Junsuk Rho
Summary: In this study, the authors investigate stress wave mitigation in composite-based woodpile phononic crystals. The study proposes a novel method of shock attenuation by adjusting the composition ratio of the materials, which results in extreme dispersive waves for efficient impact protection.
APPLIED PHYSICS LETTERS
(2022)
Article
Mechanics
Ali Hosseinkhani, Emad Panahi, Mohammad Farid Khansanami, Davood Younesian
Summary: In this paper, an auxetic tape composed of modified star-shaped unit cells is used to filter the propagation of elastic waves in two-dimensional structures. The pattern of the designed bandgaps and their capability to mitigate wave propagation is experimentally and numerically studied. It is shown that the lattice band is capable of trapping waves inside the bounded area and can remarkably suppress the propagation of waves. Numerical results and the bandgap formation obtained from Bloch's theorem are verified with the results measured from an experiment.
ARCHIVE OF APPLIED MECHANICS
(2023)
Article
Engineering, Civil
Ali Maghami, Seyed Mahmoud Hosseini
Summary: This article introduces a novel concept of using deep reinforcement learning (DRL) for the reverse design of phononic crystal (PC) beams with specific band structures. By training a deep deterministic policy gradient (DDPG) agent in a developed environment, the reverse design is simulated and a reward function is used to encourage the agent to achieve the desired bandgaps. The trained DDPG agent allows for instant generation of design parameters without unnecessary search.
ENGINEERING STRUCTURES
(2022)
Article
Physics, Fluids & Plasmas
B. L. Kim, C. Chong, S. Hajarolasvadi, Y. Wang, C. Daraio
Summary: In this study, the response of a one-dimensional phononic lattice with time-periodic elastic properties is investigated in both linear and nonlinear regimes using experimental, numerical and theoretical approaches. It is found that wave-number band gaps emerge under small-amplitude excitation, while large-amplitude responses are stabilized via the nonlinear nature of the magnetic interactions, resulting in a family of nonlinear time-periodic states. Controlling acoustic and elastic wave propagation by balancing nonlinearity and external modulation offers potential applications in signal processing and telecommunication devices.
Article
Engineering, Mechanical
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: Thanks to their extraordinary dynamic characteristics, nonlinear phononic crystals (PCs) have found invaluable academic and industrial significance, in recent years. In this paper, we investigate the roton-like behavior of PCs by introducing a nonlinear monoatomic chain with the third-neighbor interactions able to exhibit backward energy flow in the Brillouin zone. The results reveal that the roton-like behavior can lead to extraordinary characteristics in PCs and including nonlinearity can provide an extra level of control over their behavior.
NONLINEAR DYNAMICS
(2023)
Article
Chemistry, Multidisciplinary
Anastasiia O. Krushynska, Antonio S. Gliozzi, Alberto Fina, Dmitry Krushinsky, Daniele Battegazzore, Miguel A. Badillo-Avila, Monica Acuautla, Stefano Stassi, Camilla Noe, Nicola M. Pugno, Federico Bosia
Summary: Phononic materials are artificial composites with the ability to control acoustic waves in solids, their performance is determined by structure and mechanical/material properties of constituents. Dynamics of polymer phononic materials with different architectures made of thermoset and thermoplastic polymers are characterized, and the reliability of elastic and viscoelastic material models is evaluated in broad frequency ranges.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Physics, Applied
Chaoyu Sun, Ailing Song, Yanxun Xiang, Fu-Zhen Xuan
Summary: This paper proposes a phononic crystal filter to purify the ultrasonic signal in nonlinear guided wave testing. The design principle, theoretical analysis, and numerical simulations of the proposed filter are introduced, and the results demonstrate its applicability in low-frequency S0 mode Lamb wave nonlinear harmonic wave testing.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Review
Chemistry, Physical
Yiwei Wang, Xiaomei Xu, Li Li
Summary: This article summarizes the structures and tuning methods of bandgaps for piezoelectric phononic crystals (PCs), and analyzes the calculation methods. The shortcomings of current research are discussed, and future development directions are proposed.
Article
Acoustics
V. F. Almeida, V. D. Lima, J. R. F. Arruda
Summary: This work proposes the redesign of an intake muffler in a refrigerant compressor using the concept of wave attenuation bands caused by Bragg scattering to improve transmission loss. The research focuses on developing and validating numerical and experimental techniques for periodic muffler design and applying them to a real compressor muffler.
Article
Computer Science, Interdisciplinary Applications
Chengcheng Luo, Shaowu Ning, Zhanli Liu, Xiang Li, Zhuo Zhuang
Summary: This study proposes a design method for attenuating stress waves pressure using soft matrix embedded with particles. It discusses the relationship between the center frequency and width of the bandgap and the geometric and physical parameters of particle core, and explains the trend of influence by a spring oscillator model. Increasing the radius of hard core could effectively enhance the bandgap width for enhancing the effect of stress wave attenuation.
ENGINEERING COMPUTATIONS
(2021)
Article
Materials Science, Multidisciplinary
Xiao-feng Li, Shu-liang Cheng, Ran Wang, Qun Yan, Bin Wang, Yong-tao Sun, Hao Yan, Qing-xin Zhao, Ya-jun Xin
Summary: In this paper, novel two-dimensional single-phase three-ligament, four-ligament and six-ligament chiral structure models are proposed, which are easy to manufacture with few components and have good sound insulation and vibration damping performance. The dispersion information of the structure is calculated using Bloch's theorem and the finite element method. The optimized structure exhibits significantly lower bandgap and wider bandgap width, allowing for multi-frequency and broadband vibration attenuation.
RESULTS IN PHYSICS
(2023)
Article
Engineering, Mechanical
Rongjiang Tang, Taoqi Lu, Weiguang Zheng
Summary: This study aims to achieve small-size control of large wavelengths in phononic crystals. Through finite element method calculations and analysis, an ultrawide band gap has been successfully achieved. It was found that the presence of silicone rubber is crucial for obtaining low-frequency ultra-wideband gap.
JOURNAL OF VIBRATION ENGINEERING & TECHNOLOGIES
(2023)
Article
Engineering, Mechanical
Qian Geng, Lingyi Kong, Xiongwei Yang, Zhushan Shao, Yueming Li
Summary: This study proposes an easy-to-implement design of a phononic crystal pipe that utilizes attached sleeves to suppress flexural vibration. By utilizing the mechanism of Bragg scattering, a flexural wave bandgap can be obtained through periodic changes in the cross section of the sleeved pipe. The installation of the sleeves simultaneously adds mass and stiffness, resulting in parabolic variations in the bandgap edge frequencies against sleeve dimensions. The asynchronous recovery of the two frequency loci causes the bandgap to close when the sleeve covers approximately half the length of the unit cell. This feature is not observed in analyses of binary phononic crystal pipes. Equivalent models are proposed to discuss the predicted variations, and the singular dependence of bandgap closure on sleeve length is theoretically explained. Experiments validate the feasibility of attaching sleeves for flexural vibration suppression of pipes. The proposed design effectively attenuates vibration energy within the intended bandgap.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Mechanical
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: The combination of nonlinearity and electromagnetic actuation has successfully achieved the goal of actively controlling and manipulating wave propagation in phononic crystals. The research shows that electromagnetic actuation can efficiently alter the wave propagation characteristics, leading to tunability in the stop-band frequency range of phononic chains.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Nanoscience & Nanotechnology
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: This paper investigates the effect of shear deformation on wave propagation in periodic lattices with different topologies. It is found that shear deformation has a softening effect on wave propagation, shifting dispersion branches to lower frequencies and revealing previously unpredicted bandgaps.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART N-JOURNAL OF NANOMATERIALS NANOENGINEERING AND NANOSYSTEMS
(2022)
Article
Materials Science, Multidisciplinary
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: This paper investigates the phononic crystal properties of microbeams made of functionally graded materials, achieving tunable wave attenuation through the periodic arrangement of auxiliary piezoelectric springs. The results demonstrate that wave attenuation can be controlled in different frequency ranges by implementing functionally graded materials and combining it with piezoelectricity.
MECHANICS OF MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Sajad Mousavi Nejad Souq, Faramarz Ashenai Ghasemi, Mir Masoud Seyyed Fakhrabadi
Summary: This study evaluates the effects of various cross sections on the mechanical properties of Fe nanowires using molecular dynamics simulation. The results show that the tensile/compressive strength values in the bulk model are higher than in the nanowires. The compressive strength values are more sensitive to the change of the shape of the cross section compared to tensile strength values. Different cross section shapes also result in different twinning planes and Burgers vectors.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Materials Science, Multidisciplinary
Ali Narjabadifam, Babak Abazadeh, Mir Masoud Seyyed Fakhrabadi
Summary: This paper investigates the mechanical behavior of nano-spirals made of different graphyne structures under tension using molecular dynamics simulation, comparing the results with graphene nano-spirals. Five distinct deformation stages are observed, with the effects of various base structures on superelastic deformation capabilities and fracture mechanisms analyzed. It is found that the stretchability of nano-spirals increases with outer radius up to a maximum threshold, then decreases, with graphene and gamma-graphyne spirals showing clearer decrease compared to alpha- and beta-graphyne spirals.
MECHANICS OF MATERIALS
(2022)
Article
Engineering, Mechanical
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: This study aims to provide a semi-analytical model for wave propagation in fractionally damped nonlinear phononic crystals, emphasizing the importance of considering nonlinearities in modeling periodic materials and providing new insight into energy dissipation in phononic crystals.
NONLINEAR DYNAMICS
(2022)
Article
Engineering, Mechanical
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: In this study, the modified strain gradient theory is used for the first time to model two-dimensional micro-lattices of functionally graded materials. The effect of the functionally graded distribution of materials on the wave propagation and wave filtering performances of these structures is investigated.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Engineering, Mechanical
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: Thanks to their extraordinary dynamic characteristics, nonlinear phononic crystals (PCs) have found invaluable academic and industrial significance, in recent years. In this paper, we investigate the roton-like behavior of PCs by introducing a nonlinear monoatomic chain with the third-neighbor interactions able to exhibit backward energy flow in the Brillouin zone. The results reveal that the roton-like behavior can lead to extraordinary characteristics in PCs and including nonlinearity can provide an extra level of control over their behavior.
NONLINEAR DYNAMICS
(2023)
Article
Mathematics, Applied
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: Due to the intriguing effects of nonlinearity on wave propagation and dynamic properties, nonlinear phononic crystals have become a prominent research topic. However, there has been relatively little exploration of 2D planar lattices with weak nonlinearities. This study presents an active control technique using piezoelectric actuation to manipulate wave propagation in nonlinear planar lattices. By deriving governing equations and applying the Lindstedt-Poincare method, this study provides semi-analytical solutions and derives analytical nonlinear dispersion relations for these lattices for the first time. The results demonstrate the influence of piezoelectric springs on dispersion curves and wave directionality, proposing a tuning approach for controlling wave propagation characteristics and attenuation performance in nonlinear planar lattices.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2023)
Article
Physics, Multidisciplinary
Soroush Sepehri, Mahdi Bodaghi
Summary: This paper investigates the influence of Coulomb damping on the wave propagation behavior of cubically nonlinear monoatomic phononic chains. The nonlinear dispersion relation is obtained analytically using the multiple scales method and the band structure of the damped nonlinear chains is compared to the linear and nonlinear undamped chains. Coulomb damping can lead to lower dispersion frequencies in the chain due to the coupling between the amplitude and the frequency, resulting from the nonlinear nature of the chain. This study captures the effect of Coulomb damping on the wave propagation behavior of nonlinear lattices, bringing us closer to developing a comprehensive analytical model for the behavior of damped phononic crystals.
Article
Physics, Multidisciplinary
Seyed Saeed Taheri, Mir Masoud Seyyed Fakhrabadi
Summary: This research characterizes the mechanical behavior of boron nitride nanocones (BNNCs) through molecular dynamics simulations. The study shows that all elastic constants of the BNNCs depend on their apex angle, with wider ones having lower Young's and longitudinal shear moduli. However, as the apex angle of the nanocones increases, their plane-strain bulk moduli and in-plane shear constants increase. The study also reveals that Poisson's ratio decreases with an increase in the apex angle and length of the BNNCs, and shorter and sharper BNNCs have higher strain values at failure.
