| 2016 | |
| 1 | Zhang J and Wang Q (2016), Modeling and simulation of a frictional translational joint with a flexible slider and clearance, MULTIBODY SYSTEM DYNAMICS., DEC, 2016. Vol. 38(4), pp. 367-389. |
| Abstract: A finite element method for the dynamic description of multibody systems
with a frictional translational joint is presented and discussed in this work. By considering the slider deformation and the clearance size between the slider and the guide, Coulomb and Stribeck models are used to describe friction forces. The geometric constraints of the translational joints are treated as multi-unilateral constraints, and the impacts between the slider and guide are neglected when the clearance sizes are very small. A model of contact forces is established based on the penalty method and a criterion is proposed to evaluate the influence of clearance size on nodal contact forces. Time-varying contact states of nodes are determined by applying two contact detection algorithms for stick and slip, respectively. Based on kineto-elasto-dynamic method and varying penalty factors, the method avoids convergence difficulties and enforces the accuracy. Numerical results reveal the capability of the new method and the influences of small deformations of the slider, clearance size and friction forces on the dynamic response of the multibody systems with a translational joint. |
|
BibTeX:
@article{ISI:000388687500003,
author = {Zhang, Jie and Wang, Qi},
title = {Modeling and simulation of a frictional translational joint with a flexible slider and clearance},
journal = {MULTIBODY SYSTEM DYNAMICS},
year = {2016},
volume = {38},
number = {4},
pages = {367-389},
doi = {{10.1007/s11044-015-9474-7}}
}
|
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| 2014 | |
| 2 | Marin M, Mahmoud SR and Stan G (2014), INTERNAL STATE VARIABLES IN DIPOLAR THERMOELASTIC BODIES, HACETTEPE JOURNAL OF MATHEMATICS AND STATISTICS., FEB, {2014}. Vol. 43(1), pp. 15-26. |
| Abstract: The aim of our study is prove that the presence of the internal state
variables in a thermoelastic dipolar body do not influence the uniqueness of solution. After the mixed initial boundary value problem in this context is formulated, we use the Gronwall's inequality to prove the uniqueness of solution of this problem. |
|
BibTeX:
@article{ISI:000334818000002,
author = {Marin, M. and Mahmoud, S. R. and Stan, G.},
title = {INTERNAL STATE VARIABLES IN DIPOLAR THERMOELASTIC BODIES},
journal = {HACETTEPE JOURNAL OF MATHEMATICS AND STATISTICS},
year = {2014},
volume = {43},
number = {1},
pages = {15-26}
}
|
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| 3 | Oner E, Yaylaci M and Birinci A (2014), Solution of a receding contact problem using an analytical method and a finite element method, JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES., MAY, 2014. Vol. 9(3), pp. 333-345. |
| Abstract: In this study, a receding contact problem for two elastic layers
supported by a Winkler foundation is handled using two different methods such as an analytical method and a finite element method. Firstly, the problem is solved analytically using linear elasticity theory. Then, in order to solve the same problem in a different way, a finite element model of the problem is created by ANSYS software, and finite element analysis of the problem is performed. The contact stresses and the contact areas at the interfaces between punch-Layer 2 and Layer 1-Layer 2 are obtained for both solutions, and it is shown that the finite element method indicates a good agreement with the analytical method. |
|
BibTeX:
@article{ISI:000344648700004,
author = {Oner, Erdal and Yaylaci, Murat and Birinci, Ahmet},
title = {Solution of a receding contact problem using an analytical method and a finite element method},
journal = {JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES},
year = {2014},
volume = {9},
number = {3},
pages = {333-345},
doi = {{10.2140/jomms.2014.9.333}}
}
|
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| 4 | Pop N, Vladareanu L, Popescu IN, Ghita C, Gal A, Cang S, Yu H, Bratu V and Deng M (2014), A numerical dynamic behaviour model for 3D contact problems with friction, COMPUTATIONAL MATERIALS SCIENCE., NOV, 2014. Vol. 94(SI), pp. 285-291. |
| Abstract: This paper proposes a novel algorithm for the condition detection in
which the slip state transitions in a stick-slip motion, or the solution breaks down and also to study the state transition of nodes belonging to the contact area: stick, slip or open contact state. We designed a Matlab Simulink program to simulate the occurrence conditions for the slip-stick transition analysing three types of contact surface materials, with respectively 0.5, 0.75 and 0.9 friction coefficients, using finite element contact. The proposed method is able to detect the stick-slip motion and implicit the numerical instability of the model. By applying this method to control walking robots on uncertain, unknown and unstructured surfaces, the occurrence conditions for the slip-stick transition depending on the friction coefficient of contact material were determined. The presented simulations demonstrates through a numeric modelling of the dynamic behaviour of 3D contact problems with friction we can detect the slip/stick phenomenon for a walking robot motion on a uneven terrain, so it can improve the real time control in order to predict and avoid robot overthrow. (C) 2014 Elsevier B.V. All rights reserved. |
|
BibTeX:
@article{ISI:000342360000034,
author = {Pop, Nicolae and Vladareanu, Luige and Popescu, Ileana Nicoleta and Ghita, Constantin and Gal, Alexandru and Cang, Shuang and Yu, Hongnian and Bratu, Vasile and Deng, Mingcong},
title = {A numerical dynamic behaviour model for 3D contact problems with friction},
journal = {COMPUTATIONAL MATERIALS SCIENCE},
year = {2014},
volume = {94},
number = {SI},
pages = {285-291},
doi = {{10.1016/j.commatsci.2014.05.072}}
}
|
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| 2012 | |
| 5 | Ghita C, Pop N and Cioban H (2012), Quasi-Static behavior as a limit process of a dynamical one for an anisotropic hardening material, COMPUTATIONAL MATERIALS SCIENCE., FEB, 2012. Vol. 52(1), pp. 217-225. |
| Abstract: We formulate some problems modeling the local hardening behavior of a
plastic material following a Prandtl-Reuss law. Directional linear hardening, which is similar to Bauschinger's effect in metals, is characterized by an anisotropic factor. The flow process of the material is revealed by translation in the direction shown by deformation using an absolutely continuous guiding function. The possibility of choice of a plastic strain component for the mechanical system with hardening requires an algebraic factorization of the space of processes. If the quasi-static deformation is seen as a limit case of the dynamic deformation, corresponding to low speeds and low inertial forces, we obtain an existence and uniqueness result. In this context there exists an admissible plastic strain rate, as follows by choosing a permissible elastic stress as a solution for a sweeping process problem. (C) 2011 Published by Elsevier B.V. |
|
BibTeX:
@article{ISI:000297779700038,
author = {Ghita, Constantin and Pop, Nicolae and Cioban, Horia},
title = {Quasi-Static behavior as a limit process of a dynamical one for an anisotropic hardening material},
journal = {COMPUTATIONAL MATERIALS SCIENCE},
year = {2012},
volume = {52},
number = {1},
pages = {217-225},
note = {20th International Workshop on Computational Mechanics of Materials (IWCMM 20), Loughborough Univ, Loughborough, ENGLAND, SEP 08-10, 2010},
doi = {{10.1016/j.commatsci.2011.03.030}}
}
|
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| 6 | Ghita C, Pop N and Popescu IN (2012), Existence result of an effective stress for an isotropic visco-plastic composite, COMPUTATIONAL MATERIALS SCIENCE., NOV, 2012. Vol. 64, pp. 52-56. |
| Abstract: We define and present some theoretical characterizations of associated
constitutive equations for a visco-plastic deformation of a composite. Introducing of an adequate topological framework for some visco-plastic state parameters, when considered a nonlinear stress-strain relations of Prandtl-Reuss type, we obtain the existence and uniqueness results of a steady state for a composite reinforced with other inclusions. The time-dependent plastic strains of these Al based composites reinforced with SiC inclusions are then calculated as a function of inclusion volume concentration, effective stress and effective visco-plastic strain, following an dynamical yield function of power type. Viewed as a Drucker-Prager material, a selection criterion for visco-plastic strain rate, permit us a formulation as an isotropic hardening problem and their reduction to a sweeping process problem for an elastic component of the strain. In this paper a family of models for the composite deformation, defined by Halphen and Nguyen Quoc Son, enlarges the classical class of generalized standard materials, ant they are characterized by monotone-gradient flow function. These models improve the tensile process of Al based composite, in order to allow new practical solutions in civil engineering. (C) 2012 Elsevier B. V. All rights reserved. |
|
BibTeX:
@article{ISI:000308396200013,
author = {Ghita, Constantin and Pop, Nicolae and Popescu, Ileana Nicoleta},
title = {Existence result of an effective stress for an isotropic visco-plastic composite},
journal = {COMPUTATIONAL MATERIALS SCIENCE},
year = {2012},
volume = {64},
pages = {52-56},
note = {21st International Workshop on Computational Mechanics of Materials (IWCMM), Univ Limerick, Limerick, IRELAND, AUG 22-24, 2011},
doi = {{10.1016/j.commatsci.2012.03.058}}
}
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