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Following are some publications with reference to the use of ADINA. The pages give the Abstracts of some papers published since 1986 referring to ADINA. The most recent papers are listed first. All these papers may be searched using the box:
Simulating
and predicting welding solidification cracks
Wei,
Yanhong (Lab. of Adv. Welding Technol., Harbin Inst. of Technol.);
Dong, Zhibo; Liu, Renpei; Dong, Zujue Source: Jixie Gongcheng
Xuebao/Chinese Journal of Mechanical Engineering, v 40, n 7, July,
2004, p 93-98 Language: Chinese
ISSN:
0577-6686 CODEN: CHHKA2
Publisher:
Editorial Office of Chinese Journal of Mechanical Engineering
Abstract:
A computer system is developed which can predict the weld
solidification cracks for weldment in two dimensions. Firstly, the
pre-data-treatment subsystem helped users to discretize the
workpiece, calculate heat generation and the time to add or remove
the nodes of the welding molten pool, input the physical properties
of materials and generate a calculated card for final FEM
calculation. Secondly, the system transferred the calculated cards to
software package of Adina and t to complete the calculation of
thermal, strain and stress distributions. Next, the post-data
treatment section could deal with the calculated data and display the
results in featured curves, contours and 3D figures. Lastly, the
system regressed the experimental data of trans-varestraint test to
obtain the resistance curve of weld solidification cracks and had it
compared with the driving force in the same figures and thus
predicted the possibility of weld solidification cracks. The system
is completed with computer languages Visual Basic 6.0 by combining
with the matrix calculating and graphic functions of Matlab 5.3 and
Matrix VB to realize the display the graphs. (6 refs.)
Keywords: Welding - Solidification -
Cracks - Computer simulation - Strain
- Stresses - Physical properties - Finite
element method - Welds Secondary Keywords: Welding
solidification cracks - Post data treatment
3D
MRI-based multicomponent FSI models for atherosclerotic plaques
Tang,
Dalin (Mathematical Sciences Department, Worcester Polytechnic
Institute); Yang, Chun; Zheng, Jie; Woodard, Pamela K.; Sicard,
Gregorio A.; Saffitz, Jeffrey E.; Yuan, Chun Source: Annals of
Biomedical Engineering, v 32, n 7, July, 2004, p 947-960
ISSN:
0090-6964 CODEN: ABMECF
Publisher:
American Institute of Physics Inc.
Abstract:
A three-dimensional (3D) MRI-based computational model with
multicomponent plaque structure and fluid-structure interactions
(FSI) is introduced to perform mechanical analysis for human
atherosclerotic plaques and identify critical flow and stress/strain
conditions which may be related to plaque rupture. Three-dimensional
geometry of a human carotid plaque was reconstructed from 3D MR
images and computational mesh was generated using Visualization
Toolkit. Both the artery wall and the plaque components were assumed
to be hyperelastic, isotropic, incompressible, and homogeneous. The
flow was assumed to be laminar, Newtonian, viscous, and
incompressible. The fully coupled fluid and structure models were
solved by ADINA, a well-tested finite element package. Results from
two-dimensional (2D) and 3D models, based on ex vivo MRI and
histological images (HI), with different component sizes and plaque
cap thickness, under different pressure and axial stretch conditions,
were obtained and compared. Our results indicate that large lipid
pools and thin plaque caps are associated with both extreme maximum
(stretch) and minimum (compression when negative) stress/strain
levels. Large cyclic stress/strain variations in the plaque under
pulsating pressure were observed which may lead to artery fatigue and
possible plaque rupture. Large-scale patient studies are needed to
validate the computational findings for possible plaque vulnerability
assessment and rupture predictions. (56 refs.)
Keywords: Magnetic resonance imaging - Fluid
structure interaction - Diseases - Blood
vessels - Three dimensional computer graphics -
Computational methods - Incompressible flow -
Newtonian flow - Viscous flow - Finite
element method - Thickness measurement - Lipids
- Stresses - Pulsatile flow
Secondary Keywords: Stroke - Heart attack - Plaque
cap rupture - Stenosis - Cartoid artery
- Blood flow - Cariovascular diseases
Computational
modeling of flow over an ogee spillway
Chatila,
Jean (Department of Civil Engineering, Sch. of Engineering and
Architecture, Lebanese American University); Tabbara, Mazen Source:
Computers and Structures, v 82, n 22, September, 2004, p 1805-1812
ISSN:
0045-7949 CODEN: CMSTCJ
Publisher:
Elsevier Ltd
Abstract:
This paper presents an investigation into the hydraulics of regular
ogee-profile spillways. The free-surfaces of the fluid for several
flow heads as measured in the hydraulics laboratory are used as
benchmarks. The finite element computational fluid dynamics software,
ADINA, was used to predict the free surface over an ogee spillway and
thus model the flow field. Since the actual flow is turbulent the
k-ε flow model was used. For the cases considered in this
paper, ADINA predicted reasonable free surface results that are
consistent with general flow characteristics over spillways. The
results are also in close agreement with measured free-surface
profiles over the entire length of the spillway. © 2004
Elsevier Ltd. All rights reserved. (30 refs.)
Keywords: Spillways - Hydraulics - Surface
phenomena - Turbulent flow - Benchmarking
- Finite element method - Computational fluid
dynamics - Numerical analysis - Mathematical
models Secondary Keywords: Ogee-spillway -
Numerical - Experimental - Modeling
- Free surface - Finite element
A
coupled elastoplastic damage model for geomaterials
Salari,
M.R. (Dept. of Civil Environ./Arch. Eng., Univeristy of Colorado);
Saeb, S.; Willam, K.J.; Patchet, S.J.; Carrasco, R.C. Source:
Computer Methods in Applied Mechanics and Engineering, v 193, n
27-29, Jul 9, 2004, p 2625-2643
ISSN:
0045-7825 CODEN: CMMECC
Publisher:
Elsevier
Abstract:
A triaxial constitutive model is developed for elastoplastic
behavior of geomaterials, which accounts for tensile damage. The
constitutive setting is formulated in the framework of continuum
thermodynamics using internal variables. The interaction of elastic
damage and plastic flow is examined with the help of very simple
constitutive assumptions: (i) a Drucker-Prager yield function is used
to define plastic loading of the material in combination with a
non-associated flow rule to control inelastic dilatancy; (ii) elastic
damage is assumed to be isotropic and is represented by a single
scalar variable that evolves under expansive volumetric strain.
Thereby, positive volumetric deformations couple the dissipation
mechanisms of elastic damage and plastic flow which introduce
degradation of the elastic stiffness as well as softening of the
strength. The constitutive model is implemented in the finite element
program ADINA to determine the response behavior of the combined
damage-plasticity model under displacement and mixed control. A
number of load histories are examined to illustrate the performance
of the material model in axial tension, compression, shear and
confined compression. Thereby incipient failure is studied at the
material level in the form of non-positive properties of the
tangential material tensor of elastoplastic damage and the
corresponding localization tensor comparing non-associative with
associative plasticity formulations. © 2004 Elsevier B.V.All
rights reserved. (23 refs.) Keywords: Geosynthetic
materials - Elastoplasticity - Thermodynamics
- Strain - Stiffness - Tensile
strength - Plastic flow - Shear
deformation Secondary Keywords: Elastic damage -
Continuum thermodynamics - Geomaterials -
Axial tension
Finite
element developments for general fluid flows with structural
interactions
Bathe,
Klaus-Jurgen (Massachusetts Inst. of Technology); Zhang, Hou Source:
International Journal for Numerical Methods in Engineering, v 60, n
1, May 7, 2004, p 213-232
ISSN:
0029-5981 CODEN: IJNMBH
Publisher:
John Wiley and Sons Ltd
Abstract:
The objective in this paper is to present some developments for the
analysis of Navier-Stokes incompressible and compressible fluid flows
with structural interactions. The incompressible fluid is discretized
with a new solution approach, a flow-condition-based interpolation
finite element scheme. The high-speed compressible fluids are solved
using standard finite volume methods. The fluids are fully coupled to
general structures that can undergo highly non-linear response due to
large deformations, inelasticity, contact and temperature. Particular
focus is given on the scheme used to couple the fluid media with the
structures. The fluids can also be modelled as low-speed compressible
or slightly compressible media, which are important models in
engineering practice. Some solutions obtained using ADINA are
presented to indicate the analyses that can be performed. ©
2004 John Wiley and Sons, Ltd. (35 refs.) Keywords: Flow
of fluids - Deformation - Compressible flow
- Interpolation - Finite element method -
Navier Stokes equations - Numerical
methods Secondary Keywords: Discretized -
Compressible fluids - Fluid media -
Structural interactions
Computation
of blood flow in a diaphragm-type ventricular assist device
Doyle,
M. (Department of Mechanical Engineering, University of Ottawa);
Tavoularis, S.; Bourgault, Y. Source: Proceedings of the IASTED
International Conference on Biomechanics, Proceedings of the IASTED
International Conference on Biomechanics, 2003, p 92-96
ISBN-10:
0889863598
Conference:
Proceedings of the IASTED International Conference on Biomechanics,
Jun 30-Jul 2 2003, Rhodes, Greece Sponsor: IASTED
Publisher:
Int. Assoc. of Science and Technology for Development
Abstract:
The goal of this research is to advance the use of Computational
Fluid Dynamics (CFD) in modelling the operation of ventricular assist
devices (VADs) connected to the circulatory system, as a
cost-effective alternative to experimentation. An idealized VAD,
based on a design developed by a group at Brunel University, has been
chosen for this research because of the availability of experimental
and computational results. The simulations are made with the use of
the commercial finite element software package ADINA, which is among
the few available codes with fluid-structure interaction (FSI)
capabilities, as required for the modelling of fluid flows coupled
with the deformation of solid components. The present VAD model
consists of two rigid hemispherical chambers separated by a flexible
circular diaphragm. This device is attached to compliant and
resistive elements used to represent the components of the
circulatory system and is run on a closed loop. Preliminary results
show the feasibility of this approach and are, in order-of-magnitude,
in agreement with the Brunel University results. (6 refs.)
Keywords: Hemodynamics - Blood -
Computational fluid dynamics - Cardiovascular
surgery - Implants (surgical) - Biological
membranes - Computational geometry - Mathematical
models - Computer simulation
Secondary Keywords: Cardiovascular implants and devices - FEM
modeling - Computational blood flow -
Fluid-structure interaction
Quantifying
effects of controlling factors on flow and stress distribution in
stenotic arteries with lipid cores
Tang,
Dalin (Mathematical Sciences Dept., Worcester Polytechnic Institute);
Yang, Chun; Kobayashi, Shunichi; Ku, David N. Source: American
Society of Mechanical Engineers, Bioengineering Division
(Publication) BED, v 55, 2003 Advances in Bioengineering, 2003, p
53-54
ISSN:
1071-6947 CODEN: ASMBEP
Conference:
2003 ASME International Mechanical Engineering Congress, Nov 15-21
2003, Washington, DC., United States Sponsor: The Bioengineering
Division, ASME
Publisher:
American Society of Mechanical Engineers
Abstract:
2D and 3D multi-physics experiment-based nonlinear models with
fluid-structure interactions (FSI) and structure-structure
interactions (SSI) are introduced to model blood flow and
stress/strain distributions in stenotic arteries with lipid pools.
Material properties for the vessel and plaque are based on
experimental measurements and information available in the literature
(Huang et. al., 2001; Tang et. al., 2001). The Navier-Stokes
equations are used as the governing equations for the fluid.
Mooney-Rivlin models are used for both arteries and lipid cores. A
well-tested finite element package ADINA is used to solve the models
to perform flow and stress/strain analysis. Our results indicate that
artery plaque stress/strain distributions are affected considerably
(50%-400% or even more) by vessel material properties, stenosis
severity and eccentricity, tube axial pre-stretch, pressure
conditions, lipid core material property, size, position and
geometry, and fluid-structure and structure-structure (vessel wall
and lipid core) interactions. Differences in model assumptions and
controlling factor specifications must be taken into consideration
when interpreting the significance of computational results. (3
refs.) Keywords: Blood vessels - Finite
element method - Hemodynamics - Lipids
- Mathematical models - Navier Stokes equations
- Nonlinear systems - Strain -
Stresses Secondary Keywords: Atherosclerosis -
Fluid-structure interaction - Artery -
Stenosis - Plaque cap rupture - Stroke
- Heart - Blood flow
Dynamic
behaviour of compliant towers in deep sea
Clauss,
Gunther F. (Inst. of Land and Sea Transportation, Division of Ocean
Engineering, Technical University of Berlin); Lee, June Young Source:
Proceedings of the International Conference on Offshore Mechanics and
Arctic Engineering - OMAE, v 1, 2003, p 317-327
CODEN:
PIOSEB
Conference:
22nd International Conference on Offshore Mechanics and Arctic
Engineering; Offshore Technology Ocean Space Utilization, Jun 8-13
2003, Cancun, Mexico Sponsor: ASME;American Concrete
Institute;ASCE;Associazione Italiana di Ingegneria Offshore e
Marina;Brazilian Society of Naval Architects
Publisher:
American Society of Mechanical Engineers
Abstract:
For oil and gas production in deep water (> 500m) compliant
structures are designed. By dedicated reduction of stiffness and
optimization of mass (including added mass contributions) the
fundamental period is tuned to about 30s, which is well above the
period range of significant wave energy. This paper presents the
results of a comprehensive numerical analysis of the hydroelastic
behaviour of compliant towers in deep water, investigating the
dynamic response of a flexible structure in a given sea state. The
numerical program system is based on ADINA with an integrated
hydrodynamic module for wave/structure interaction. Nonlinear effects
of viscous forces are considered using Morison's vector equation. In
addition nonlinear characteristics of soil/structure interaction are
also included according to API regulations. At first, for
verification of the program system, the numerical results of a
monotower are compared to analytical solutions obtained by modal
analysis of the structure in regular and irregular seas. Based on the
validated program a compliant tower installed in 503 m water in the
Gulf of Mexico (Baldpate tower) is modeled in 3D, and the
characteristic dynamic behavior is evaluated. Finally, the tower is
exposed to a real "freak" wave (the 25.6m high New Year
Wave which has been registered at the North Sea Draupner platform on
January 1, 1995), and the associated loads and motions are evaluated.
(19 refs.) Keywords: Ocean structures -
Towers - Flexible structures - Stiffness
- Structural analysis - Offshore oil well
production - Water wave effects - Fluid
structure interaction - Soil structure interactions
- Computer programming - Structural optimization
- Finite element method - Modal
analysis Secondary Keywords: Compliant towers -
Harmonic excitations
Tensions
and deformations of WC-Co cermets and 17-4 PH steel vacuum brazed
joints
Nowacki,
Jerzy (Institute of Materials Engineering, Technical University of
Szczecin); Kawiak, Michal Source: Journal of Materials Processing
Technology, v 143-144, n 1, Dec 20, 2003, p 294-299
ISSN:
0924-0136 CODEN: JMPTEF
Publisher:
Elsevier Ltd
Abstract:
Analysis of the properties of WC-Co cermets and precipitation
hardening stainless steel of 17-4 PH type vacuum brazed joints has
been presented. The joints are used in a large-dimension-spinning
nozzle for polyethylene granulation in that considerable strength and
ductility of the joints is required. The results of mechanical
properties of the joint tests were a base for further numerical
investigation. Shearing tests of the joints have been done on
specimens based on the spinning nozzle brazed joint model. They have
been executed using a special shearing test device. Numerical
calculation of tensions and deformations of the joints have been made
by means of the finite element method of the ADINA system. Influence
of the geometrical parameters of the joints like the connection
thickness as well as a fixed load on stresses and displacements of
the joints have been analysed. Results of the experimental test were
the base for identification and verification of the theoretical model
parameters. The thickness of the joints has essential influence on
the values of local stress and the significant influence on the joint
rigidity. In case of the considered joints, the local stress
differences have been even a few hundred percent, depending on a
fixed load manner. © 2003 Elsevier Science B.V. All rights
reserved. (10 refs.) Keywords: Cermets -
Deformation - Stainless steel -
Precipitation (chemical) - Hardening -
Polyethylenes - Shearing - Compressive
stress - Vacuum brazing - Finite element
method Secondary Keywords: Shearing tests
Universal
trellis codes for diagonally layered space-time systems
Matache,
Adina (Dept. of Electrical Engineering, University of California);
Wesel, Richard D. Source: IEEE Transactions on Signal Processing, v
51, n 11, November, 2003, p 2773-2783
ISSN:
1053-587X CODEN: ITPRED
Publisher:
Institute of Electrical and Electronics Engineers Inc.
Abstract:
Foschini's diagonally layered space-time transmission system known
as D-BLAST is an architecture designed for a Rayleigh fading
environment using multiple element antenna arrays at both the
transmit and receive sites to achieve very high spectral
efficiencies. In this paper, we propose a simple coding technique for
D-BLAST that uses a single trellis code with finite-trace-back
Viterbi decoding. We examine the performance of universal trellis
codes that are designed to have a distance structure that is matched
to the periodic signal-to-noise ratio (SNR) variation of the channel
created by D-BLAST, under the assumption that the channel is static
during one burst but may change from burst to burst. We show that a
universal 64-state trellis code on a 2 × 2 D-BLAST system
with long enough blocklengths displays universal behavior working on
almost every 2 × 2 channel with at least the mutual
information required by a standard 64-state AWGN trellis code. The
only 2 × 2 channel where more mutual information is
required is a certain rotation of the zero eigenvalue channel. We
also present 4 × 4 and 8 × 8 examples. (27
refs.) Keywords: Trellis codes - Computer
architecture - Rayleigh fading - Decoding
- Signal to noise ratio - White noise -
Eigenvalues and eigenfunctions - Communication
channels (information theory) - Encoding (symbols)
- Convolutional codes Secondary Keywords: Universal
trellis codes - Space-time coding - Pre-survivor
processing - Threaded space-time
architecture
Three-dimensional
transient finite element analysis of the laser enamelling process and
moving heat source and phase change considerations
Nisar,
A. (Manufacturing Division, Department of Mechanical Engineering,
UMIST); Schmidt, M.J.J.; Sheikh, M.A.; Li, L. Source: Proceedings of
the Institution of Mechanical Engineers, Part B: Journal of
Engineering Manufacture, v 217, n 6, 2003, p 753-764
ISSN:
0954-4054 CODEN: PIBMEU
Publisher:
Professional Engineering Publishing Ltd.
Abstract:
A finite element model has been developed to determine the
temperature distribution generated during a high power diode laser
(HPDL) tile grout sealing process. Because of the complexity of the
process, which involves five different materials in a complicated
geometrical arrangement, finite element (FE) numerical simulation
using ADINA rather than an analytical system has been used to model
the temperature profile. The analysis has involved simulation of the
three-dimensional transient temperature field produced by a laser
beam with constant power scanning over the glazed enamel surface at
constant speeds. Latent heat effects due to melting and
solidification of the glazed enamel have been taken into account in
the FE model, thereby facilitating a more realistic thermal analysis.
Experimental validation of the FE predicted temperature profile has
also been presented. The results show that both the FE predicted
temperatures and those determined experimentally are in close
agreement with each other. The effect of varying process parameters
on temperature profiles is discussed to facilitate prediction of
optimized process parameters. (14 refs.) Keywords: High
power lasers - Semiconductor lasers - Enameling
- Temperature distribution - Transients -
Laser beams - Thermoanalysis - Finite
element method - Computer simulation
Secondary Keywords: Transient temperature fields
Performance
analysis for thermo-elastic-hydrodynamic lubrication of thrust
bearing with pins and double layer system
Wu,
Zhong-De (Sch. of Mechatronic Eng., Harbin Inst. of Technol.); Zhang,
Hong; Ren, Zhong-Hai; Wang, Li-Qin; Qu, Da-Zhuang; Qi, Yu-Lin Source:
Harbin Gongye Daxue Xuebao/Journal of Harbin Institute of Technology,
v 35, n 1, January, 2003, p 81-84 Language: Chinese
ISSN:
0367-6234 CODEN: HPKYAY
Publisher:
Harbin Institute of Technology
Abstract:
The thermo-elastic-hydrodynamic lubrication performance of Three
Gorges test thrust bearing with pins and double layer system for
Alstom has been analyzed by the finite element methods. The
lubrication calculation is programmed with the finite element
methods. Together with the function of structural finite element
program ADINAT and ADINA, a complete software of the
thermo-elastic-hydrodynamic(TEHD) lubrication performance analysis is
obtained, where the physical model includes lubricating oil film,
thrust bearing, runner and thrust head. The
thermo-elastic-deformation of thrust bearing and runner is analyzed
with the program ADINA(T). The calculated results are compared with
the measured ones in real operation. It shows that calculated
characteristics are coincident with the experimental measurement, the
pins and double layer system used in the test model has the advantage
to control the thermal and elastic deformation of the pad, and the
elasticity of the optimized pins further allows equalizing a
significant part of the runner deformation. (4 refs.)
Keywords: Thrust bearings - Lubrication -
Control - Deformation - Elasticity
- Finite element method -
Elastohydrodynamics Secondary Keywords: Runner and
thrust head - Thermoelastichydridynamic - Double
layer system - Lubricating oil film - Thermal
and elastic deformation
Some
aspects of modelling of metal forming processes
Gierzynska-Dolna,
M. (Technical University of Czestochowa); Lacki, P. Source: Computers
and Structures, v 81, n 8-11, May, 2003, p 605-613
ISSN:
0045-7949 CODEN: CMSTCJ
Publisher:
Elsevier Science Ltd
Abstract:
In the paper some numerical simulations of metal forming processes
have been described. An attention has been paid to the problems
occurring during the simulation processes. An approach to modelling
of wear and friction has been presented. The possibility of assessing
of a wear value by the basic wear parameters has been shown. The
attention has also been paid to both sticking and sliding zones.
Tools are very important during the designing process. Therefore, as
an example, the possibility of analysis both the tools and a forging
in an extrusion process has been shown. The numerical analysis has
been performed using the ADINA System. © 2003 Elsevier
Science Ltd. All rights reserved. (12 refs.)
Keywords: Metal forming - Wear of materials
- Friction - Metal extrusion - Deformation
- Finite element method Secondary Keywords: Contact
surfaces
Nonlinear
analysis of barge crush behavior and its relationship to impact
resistant bridge design
Consolazio,
Gary R. (Department of Civil Engineering, University of Florida);
Cowan, David R. Source: Computers and Structures, v 81, n 8-11, May,
2003, p 547-557
ISSN:
0045-7949 CODEN: CMSTCJ
Publisher:
Elsevier Science Ltd
Abstract:
Bridge structures crossing navigable waterways must not only be
designed to resist gravity, wind, and earthquake loads, but must also
be capable of resisting ship and barge collision loads. Design
specifications used both in the US and internationally employ
empirical models of vessel crush behavior to produce codified
procedures for computing equivalent static design loads due to vessel
impact. In this paper, the ADINA finite element code is used to
compute force-deformation relationships for several hopper barge
crushing scenarios. Results obtained from the nonlinear finite
element crush analyses are then compared to empirical crush models
found in bridge design specifications. © 2003 Elsevier
Science Ltd. All rights reserved. (13 refs.)
Keywords: Structural design - Bridges -
Impact resistance - Structural loads -
Deformation - Finite element method
Secondary Keywords: Barge impact
Design
analysis of the support structure stressed by large superconducting
coils for a plasma fusion experiment
Jaksic,
N. (Max-Planck-Inst. for Plasmaphysics, EURATOM Association);
Simon-Weidner, J. Source: Computers and Structures, v 81, n 8-11,
May, 2003, p 697-714
ISSN:
0045-7949 CODEN: CMSTCJ
Publisher:
Elsevier Science Ltd
Abstract:
A long term task of design analysis for a prototype machine, used in
plasma fusion research, is described in this paper. The core part of
each plasma fusion experiment, the superconducting coils and their
surrounding structure, are under consideration here. Specificity and
complexity of the task are discussed as well. The R and D activities
on the structural system of the experimental device were done in a
time spread of over 10 years. For the numerical simulation and
analysis of the phenomena inside the structure, the ADINA code was
chosen right from start. This decision was mainly guided considering
the efficiency of ADINA in solving nonlinear problems with a large
number of degrees of freedom. The ADINA code is still most commonly
used for numerical simulations on the current project which is
presently in the state of manufacturing. © 2003 Elsevier
Science Ltd. All rights reserved. (20 refs.)
Keywords: Superconducting materials - Plasma
applications - Fusion reactions - Stress
analysis - Structural design - Finite element
method - Problem solving - Computer
simulation Secondary Keywords: Plasma fusion
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