Article
Engineering, Mechanical
Jimmy S. Issa
Summary: The study investigates the use of a nonlinear absorber for the reflection of travelling waves in a slender bar, determining three different regimes of influence on the absorber motion and discussing the changes in system linear response. Both analytical results and numerical solutions show good agreement.
NONLINEAR DYNAMICS
(2022)
Article
Engineering, Mechanical
Weiting Chen, Xing Tan, Junhan An, Hanbo Shao, Deli Liang, Huan He
Summary: Piezoelectric shunting vibration absorber (PSVA) has attracted significant attention recently. Nonlinearity exists widely in practice, even though a linear host system was the original design intention. This study constructs a nonlinear host system with a PSVA to address the issue of applying a predesigned PSVA under the assumption of a linear host system to nonlinear vibration systems. Results show that the predesigned shunting circuit under the linear host system assumption not only works effectively, but also worsens the stability of the host system. The particle swarm algorithm is applied to determine the proper shunting circuit of the PSVA to efficiently suppress the resonant peak of the host system.
NONLINEAR DYNAMICS
(2023)
Article
Mathematics
Francisco Beltran-Carbajal, Hugo Francisco Abundis-Fong, Luis Gerardo Trujillo-Franco, Hugo Yanez-Badillo, Antonio Favela-Contreras, Eduardo Campos-Mercado
Summary: This article addresses the online frequency estimation of forced harmonic vibrations on a building-like structure, using a nonlinear flexible vibration absorber. It presents algebraic formulae to compute the harmonic excitation frequency on the nonlinear vibrating mechanical system using solely available measurement signals. The fast algebraic frequency estimation allows the online tuning of a semi-active dynamic vibration absorber to achieve a high attenuation level of undesirable vibrations.
Article
Automation & Control Systems
Sheng Hao, Yuh Yamashita, Koichi Kobayashi
Summary: In this article, a nonlinear active dynamic vibration absorber based on passivity-based energy shaping control is proposed. The proposed method can effectively control vibrations excited by force and velocity disturbances simultaneously. The control law utilizes the relative displacement and velocity of the vibration system, which can be easily measured by sensors. The parameter design of the controller converts the nonlinear dynamic vibration absorber into a desired system with multiple virtual skyhook dampers. The effectiveness of the proposed controller is verified through simulations on a cart-pendulum system.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Engineering, Mechanical
Chengen Wang, Judith D. Brown, Aryan Singh, Keegan J. Moore
Summary: This research proposes a novel two-dimensional nonlinear vibration absorber (2DNVA) to reduce the motion of flexible structures with multiple low-frequency modes in multiple directions. The 2D-NVA consists of two low-mass bodies, housing and impactor, installed on the linear primary structure with strong and weak coupling stiffness. The nonlinearity arises through contact and sliding friction between the interior of the housing and impactor, and it is shown to dramatically reduce motion in both directions of a two-dimensional linear structure under varying impulsive excitations.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Mathematics
Yiu-Yin Lee
Summary: This study investigates the effect of chaotic vibration on the sound absorption of a curved perforated panel, which has not been previously explored. By considering panel impedance and perforation impedance, a sound absorption formula is derived. Various chaotic vibrational responses are generated using numerical integration method to compute the corresponding sound absorptions, revealing interesting findings not observed in previous studies.
Article
Acoustics
Feng Qian, Lei Zuo
Summary: This study investigates the exact nonlinear dynamics of a simply-supported beam carrying a nonlinear spring-inerter-damper energy absorber for primary resonance vibration reduction. The study found that various parameters of the system, such as the location, spring stiffness, inertial mass, and damping of the nonlinear vibration absorber, can significantly influence the beam dynamics. The results also highlight the importance of considering nonlinear boundary conditions at the spring-inerter-damper location to accurately estimate nonlinear frequency responses.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Engineering, Mechanical
Giuseppe Habib, Alberto Epasto
Summary: This study addresses the implementation of the nonlinear tuned vibration absorber (NLTVA) to suppress shimmy vibration in towed wheels. By adopting a modified straight tangent tire model, stability analysis showed that the NLTVA improves the wheel's equilibrium stability significantly. Bifurcation analysis revealed large bistable regions threatening system safety, but adding intentional softening nonlinearity in the absorber restoring force characteristic eradicates these regions and reduces shimmy oscillation amplitude in the unstable region. Quasiperiodic motions were also identified, but their practical relevance seems marginal.
NONLINEAR DYNAMICS
(2023)
Article
Acoustics
Oleg Gaidai, Yu Wu, Ivan Yegorov, Panagiotis Alevras, Junlei Wang, Daniil Yurchenko
Summary: The paper investigates a strategy of nonlinear vibration mitigation using a passive absorber for a variable length pendulum. Numerical studies validate the proposed strategy and demonstrate high performance of the nonlinear passive absorber when properly tuned.
JOURNAL OF VIBRATION AND CONTROL
(2022)
Article
Engineering, Multidisciplinary
Shibo Wang, Bin Tang
Summary: This paper presents a method for estimating the backbone curves of stiffness nonlinearity in a nonlinear vibration absorber, using the Hilbert vibration decomposition method to obtain the curves of asymmetric systems, successfully applied to engineering structures.
Article
Engineering, Mechanical
Guilherme Rosa Franzini
Summary: Vortex-induced vibration (VIV) is a flow-induced vibration phenomenon of importance in offshore engineering. This study focuses on the numerical analysis of an elastic rotative nonlinear vibration absorber (ERNVA) for passive suppression of VIV, finding that ERNVA can significantly decrease oscillation amplitude and suppress VIV within a certain range of reduced velocities.
NONLINEAR DYNAMICS
(2021)
Article
Engineering, Mechanical
Kevin Dekemele, Giuseppe Habib, Mia Loccufier
Summary: Conventional nonlinear energy sinks (NES) are a robust alternative to linear vibration absorbers, with a larger efficient frequency bandwidth but limited efficiency for a small energy range. To overcome this, this paper proposes an unconventional stiffness characteristic to increase the energy bandwidth. Comparisons with traditional NES and TMD are made based on slow invariant manifolds, showing that the newly proposed NES can be robust regarding energy and frequency uncertainty.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Engineering, Mechanical
Ashutosh Shirude, C. P. Vyasarayani, Anindya Chatterjee
Summary: The study investigates a model with a primary and secondary system, demonstrating that even an imprecisely tuned secondary system can effectively stabilize the primary system. Simplifying insights obtained through methods such as harmonic balance lead to useful approximate formulas for practical use.
NONLINEAR DYNAMICS
(2021)
Article
Acoustics
Yuhao Zhao, Jingtao Du, Yilin Chen, Yang Liu
Summary: This research focuses on the effects of nonlinear vibration absorbers in beam structures and their impact on dynamic behavior, adjusting parameters of NVAs can optimize vibration suppression of the beam structure.
JOURNAL OF VIBRATION AND CONTROL
(2022)
Article
Acoustics
Ju-Hyok Kim, Jong-Hyok Ri, Hyok Jang, Chol-Ung Choe
Summary: This article introduces the centrifugal pendulum vibration absorber and the significant role of geometric nonlinear damping in reducing torsional vibrations in machines. The research findings suggest that geometric nonlinear damping can effectively eliminate multistability and hysteresis in steady states.
JOURNAL OF SOUND AND VIBRATION
(2024)
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)