A fully coupled thermo-viscoelastic finite element model for self-folding shape memory polymer sheets

This paper proposes a fully coupled three-scale finite element model for the mechanical description of an alumina/magnesium alloy/epoxy composite inspired in the mechanics and architecture of wood cellulose fibres. The constitutive response of the composite (the large scale continuum) is described by means of a representative volume element (RVE, corresponding to the intermediate scale) in which the fibre is represented as a periodic alternation of alumina and magnesium alloy fractions. Furthermore, at a lower scale the overall constitutive behavior of the alumina/magnesium alloy fibre is modelled as a single material defined by a large number of RVEs (the smallest material scale) at the Gauss point (intermediate) level. Numerical material tests show that the choice of the volume fraction of alumina based on those volume fractions of crystalline cellulose found in wood cells results in a maximisation of toughness in the present bio-inspired composite.

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A predictive tool to evaluate disk brake squeal using a fully coupled thermo-mechanical finite element model

International Journal of Vehicle Design ◽

10.1504/ijvd.2009.027118 ◽

2009 ◽

Vol 51 (1/2) ◽

pp. 124 ◽

Cited By ~ 23

Author(s):

Muhammad Zahir Hassan ◽

Peter C. Brooks ◽

David C. Barton

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Element Model ◽

Brake Squeal ◽

Predictive Tool ◽

Disk Brake ◽

Fully Coupled

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Numerical Simulation of Solar Array with Shape Memory Alloy in Active Vibration Control

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.29-32.589 ◽

2010 ◽

Vol 29-32 ◽

pp. 589-595

Author(s):

Yong Liang Zhang ◽

Shou Gen Zhao ◽

Lun Long ◽

Kang Li

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Shape Memory ◽

Vibration Control ◽

Closed Loop ◽

Active Vibration Control ◽

Element Model ◽

Solar Array ◽

Feedback Signal ◽

Control Laws

The objective of this study is to develop a general design scheme for shape memory alloys (SMA) intelligent structure. The scheme involves dynamic modeling and closed-loop simulation in a finite element environment. First, the structure of multi-body finite element model simulating the real solar array is established. SMA wire is appended on the model. The physical value of the strain, displacement, velocity and acceleration at the sensors locations separately is acted as the feedback signal. The value is multiplied by the control gain to calculate the voltage inputted to SMA wire. The finite element model is then modified to accept control laws and perform closed-loop simulations. Finally numerical examples have demonstrated the efficiency of the vibration control.

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Thermomechanical Modelling and Experimental Testing of a Shape Memory Alloy Hybrid Composite Plate

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.59.41 ◽

2008 ◽

Vol 59 ◽

pp. 41-46 ◽

Cited By ~ 5

Author(s):

Federica Daghia ◽

Gabriella Faiella ◽

Vincenza Antonucci ◽

Michele Giordano

Keyword(s):

Finite Element ◽

Shape Memory Alloy ◽

Finite Element Model ◽

Shape Memory ◽

Functional Properties ◽

Hybrid Composite ◽

Experimental Testing ◽

Element Model ◽

Electrical Heating ◽

Simultaneous Generation

Shape memory alloys (SMA) exhibit functional properties associated with the shape memory effect, responsible of the SMA shape recovery after a cycle of deforming-heating and of a simultaneous generation of mechanical work. Composite systems incorporating SMA wires have the ability to actively change shape and other structural characteristics. The functional properties of such adaptive composites are related to the martensitic transformation in the SMA elements and to the constraining behaviour that the composite matrix has on the SMA wires. In this work the behaviour of a shape memory alloy hybrid composite (SMAHC) is numerically and experimentally investigated. A plate was fabricated using prestrained SMA wires embedded in an epoxy resin pre preg glass fibres composite system. Upon calorimetric and mechanical material characterization, a finite element model was used in order to predict the structural behaviour of the SMAHC. In the experimental tests, the plate was clamped at one side and actuated via electrical heating. Temperature and displacement data were collected and compared with the prediction of the finite element model. The results show that the model is able to capture the shape change in the actuation region, although a thorough description of the SMAHC behaviour requires further modelling work, including the simulation of the SMA loading history during composite manufacturing.

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Fully coupled finite element model for dynamics of partially saturated soils

Soil Dynamics and Earthquake Engineering ◽

10.1016/j.soildyn.2009.03.002 ◽

2009 ◽

Vol 29 (9) ◽

pp. 1294-1304 ◽

Cited By ~ 14

Author(s):

Nadarajah Ravichandran

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Element Model ◽

Saturated Soils ◽

Partially Saturated ◽

Partially Saturated Soils ◽

Fully Coupled

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Thermo-piezo-elastic analysis of amplified piezoceramic actuators using a refined one-dimensional model

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x17721026 ◽

2017 ◽

Vol 29 (17) ◽

pp. 3482-3494 ◽

Cited By ~ 1

Author(s):

Enrico Zappino ◽

Erasmo Carrera

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Structural Model ◽

Element Model ◽

Elastic Analysis ◽

One Dimensional ◽

Piezoelectric Effects ◽

Carrera Unified Formulation ◽

Strain Stress ◽

Fully Coupled

The thermo-piezo-elastic analysis of amplified piezoceramic actuators is presented in this article. A refined one-dimensional multi-field finite element model, based on the Carrera Unified Formulation, has been developed. Thermal and piezoelectric effects have been included in the structural model and a fully coupled thermo-piezo-elastic analysis has been performed. The finite element model has been assessed by comparing it with results from open literature The model has also been used to perform the analysis of complex amplified piezoceramic actuators. These actuators are able to amplify the displacements produced by piezoceramic material, but they suffer from high deformations when they undergo high thermal loads. An accurate thermal analysis has been performed to evaluate the strain/stress field. The results show the accuracy of the present model and its capabilities in multi-field analyses.

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