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Showing 1 to 17 of 17 for “"Nonlinear damping"”.
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Dynamic instabilities in a system with geometrically nonlinear damping and stiffness
… of coupled oscillators possessing strongly nonlinear stiffness and damping is examined. The system consists of a linear oscillator coupled to a strongly nonlinear, light attachment, where the nonlinear terms of the system are realized due to geometric effects. It is shown that the effects of …
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A simplified representation of damping force in lumped-parameter systems with linear and nonlinear damping
… analysis techniques which determine the damping coefficients for each sub-system in the mathematical model of linear multi-degree-of-freedom systems, and to determine modal dissipation functions for nonlinear systems. For the purpose of this study, typical aerospace vehicle structure is …
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Model reduction of linear and nonlinear systems using balancing methods
… system in that of a spring-mass system with nonlinear damping is studied using the analysis set forth by J.Scherpen [11] and A.Newman [8]. The connection between linear and nonlinear balancing techniques is established and possible existant methods that reduce the complexity of the analysis …
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Strongly Stable and Accurate Numerical Integration Schemes for Nonlinear Systems in Atmospheric Models
Nonlinearity accompanied with stiffness in atmospheric boundary layer physical parameterizations is a well-known concern in numerical weather prediction (NWP) models. Nonlinear diffusion equations, furthermore, are a class of equations which are extensively applicable in different fields of science …
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Ship Rolling Motion Subjected to Colored Noise Excitation
In this research the stochastic nonlinear dynamic behaviors and probability density function of ship rolling are studied by nonlinear dynamic method and probability theory. The probability density function of rolling response is evaluated through solving the stochastic differential equations by …
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Development of a Novel Controllable Seismic Isolation System Based on Negative Stiffness Concept
… field. Firstly, the beneficial effects of nonlinear damping and stiffness on seismic protection are investigated in the form of proposing a modified ASNSD with open-loop control. It has attractive advantages in reducing the transmissibility during the resonance region without increasing …
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Adaptive control of hypersonic vehicles in presence of actuation uncertainties
… proposed class of controllers. In addition, a nonlinear damping term is added to the adaptive law to further improve the stability characteristics. It is shown here that the adaptive controllers developed above are well suited for command tracking in hypersonic vehicles (HSV) in the presence of …
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Constructive utilization of intentional nonlinearity in systems of coupled micro/nanomechanical resonators
… of the linear dynamics while the inherent nonlinearity of these systems is either neglected or considered as unwanted. In some works nonlinear effects are taken into account, but these are considered as perturbations of linear effects, and mostly explored in the regime of weakly nonlinear …
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Combined Time and Frequency Domain Approaches to the Operational Identification of Vehicle Suspension Systems
… the basis for the development of an accurate nonlinear simulation of the quarter car test rig. A comprehensive understanding of the quarter car experimental test rig dynamics is obtained before operational identification is implemented. This provides a means of validating the suspension …
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Nonlinear Vibrations of Cantilever Beams and Plates
A study of the nonlinear vibrations of metallic cantilever beams and plates subjected to transverse harmonic excitations is presented. Both experimental and theoretical results are presented. The primary focus is however on the transfer of energy between widely spaced modes via modulation. This …
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An Investigation into Nonlinear Random Vibrations based on Wiener Series Theory
… society’s technological evolution, the study of nonlinear systems in engineering and sciences has become a vital research area. Aiming to contribute in this field, this thesis investigates the behaviour of nonlinear systems using the ‘Wiener theories’. As a useful example the Duffing oscillator …
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Analytical and Numerical Methods Applied to Nonlinear Vessel Dynamics and Code Verification for Chaotic Systems
… Melnikov's method has been applied to several nonlinear ship dynamics models, which are related to the new generation of stability criteria in the International Maritime Organization (IMO). The advantage of this extended Melnikov's method is it overcomes the limitation of small damping that is …
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Prediction of Limit Cycle Oscillation in an Aeroelastic System using Nonlinear Normal Modes
There is a need for a nonlinear flutter analysis method capable of predicting limit cycle oscillation in aeroelastic systems. A review is conducted of analysis methods and experiments that have attempted to better understand and model limit cycle oscillation (LCO). The recently developed method of …
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An investigation of vibration isolation systems using active, semi-active and tunable passive mechanisms, with applications to vehicle suspensions
… force generator along with passive damping and spring elements, is mathematically modeled based on fundamental physical laws and taking into account the generator dynamics. Complete vibration isolation characteristics of the hybrid active control system are evaluated for various …
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Material and Damping Characterization of Discretized Adhesive Tapes in Cantilever Beams undergoing Free and Forced Vibration
… investigating the effectiveness of discretized damping tapes applied to a cantilever beam subjected to free and forced vibrations. The work is divided into three main sections. First, we performed material characterization of the viscoelastic (VE) pressure sensitive adhesive layer of the damping …
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Intentional nonlinearity in the small scale with applications to atomic force microscopy (AFM) and mass sensing
… the framework of linear dynamics, and incidental nonlinearity was suppressed by design. More recently, researchers have intentionally incorporated nonlinearity in the design of such devices in order to exploit the rich nonlinear behavior. Some of the nonlinear phenomena that researchers aim to …
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Experimental and Computational Study of Vibration-Based Energy Harvesting Systems for Self-Powered Devices
Energy harvesting of ambient and aeroelastic vibrations is important for reducing the dependence of wireless sensing and networks on batteries. We develop a configuration for a piezoelectric energy harvester with the capability to wirelessly communicate vibration measurements while using those …