ADINA Publications

Page 18

The Theory used in ADINA is richly documented in the following books by K.J. Bathe and co-authors


Finite Element Procedures
 

Finite Element Procedures in Engineering Analysis

Numerical Methods in Finite Element Analysis
 


The Mechanics of Solids and Structures — Hierarchical ...


The Finite Element Analysis of Shells — Fundamentals


Inelastic Analysis of Solids and Structures

 
 
To Enrich Life
(Sample pages here)
 

 

Following are more than 700 publications — that we know of — 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:

(latest on Page 43)
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Finite element analysis of fluid flows fully coupled with structural interactions

Bathe, Klaus-Jurgen (Massachusetts Inst of Technology); Zhang, Hou; Ji, Shanhong Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 1-16

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: Some advances in capabilities for analysis of fluid flows fully coupled with structural interactions are presented. Incompressible Navier-Stokes and compressible Navier-Stokes or Euler fluids and the full interaction with structures undergoing large deformations, nonlinear material response and contact conditions can be considered. The analysis capabilities are available in the ADINA System, and are integrated within computer-aided design using the available ADINA modeler and CAD interfaces. Various analysis cases are presented to illustrate the solution capabilities. (10 refs.)

Keywords:  Flow of fluids  -  Structures (built objects)  -  Finite element method  -  Structural analysis  -  Compressible flow  -  Computer simulation  -  Computational fluid dynamics  -  Computer aided design  -  User interfaces

Secondary Keywords:  Structural interactions  -  Navier-Stokes fluids  -  Euler fluids

 

 

Numerical analysis of moving orthotropic thin plates

X. Wang

Institute of Paper Science and Technology, 500 10th Street, N.W., Atlanta, GA 30318, USA

Computers and Structures, 70:467-486, 1999

Abstract: A mixed finite element formulation based on the Mindlin-Reissner plate theory is developed for a moving orthotropic thin plate. The finite element interpolations are selected according to MITC (mixed interpolated tensorial components) plate bending elements, which have recently been proven to satisfy, numerically, the inf-sup condition. We show, with a few test cases, that the proposed formulation is reliable for both frequency and transient dynamics analyses, and that no shear locking is encountered.

Keywords: Mixed formulation — Finite Element — Mindlin-Reissner plate theory — Moving material — Orthotropic — Dynamics

 

 

Computational simulation of turbulent mixing with mass transfer

X. Wang, Z. Feng, L.J. Forney

Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta, GA 30318, U.S.A.

Computers and Structures, 70: 447-465, 1999

Abstract: In this paper, we present a series of computational simulations of three-dimensional turbulent mixing with mass transfer for various pipe mixing arrangements. The simulations are carried out with the ADINA software, in which general-purpose finite element and finite volume formulations along with the k-Ε turbulent model are used for incompressible Navier-Stokes flows with mass transfer. Based on the predicted pressure and velocity profiles and the standard deviation of tracer (or fiber) spatial distributions at certain distances downstream from the injection point, we compare the mixing performances of various transverse, concentric, and multijet mixers as well as four silo mixing units. In addition, we deduce certain design information pertaining to different mixing configurations.

Keywords: Keywords: Turbulent mixing — Mass transfer — Finite element — Silo — Jet — Pipe

 

 

Balloon-Artery Interactions During Stent Placement : A Finite Element Analysis Approach to Pressure, Compliance, and Stent Design as Contributors to Vascular Injury

Campbell Rogers, David Y. Tseng, James C. Squire and Elazer R. Edelman

Cardiac Catheterization Laboratory and Coronary Care Unit, Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Mass. and
Harvard-MIT Division of Health Science and Technology, Massachusetts Institute of Technology, Cambridge, Mass.

Circulation Research, 84;378-383, 1999

Abstract: Endovascular stents expand the arterial lumen more than balloon angioplasty and reduce rates of restenosis after coronary angioplasty in selected patients. Understanding the factors involved in vascular injury imposed during stent deployment may allow optimization of stent design and stent-placement protocols so as to limit vascular injury and perhaps reduce restenosis. Addressing the hypothesis that a previously undescribed mechanism of vascular injury during stent deployment is balloon-artery interaction, we have used finite element analysis to model how balloon-artery contact stress and area depend on stent-strut geometry, balloon compliance, and inflation pressure. We also examined superficial injury during deployment of stents of varied design in vivo and in a phantom model ex vivo to show that balloon-induced damage can be modulated by altering stent design. Our results show that higher inflation pressures, wider stent-strut openings, and more compliant balloon materials cause markedly larger surface-contact areas and contact stresses between stent struts. Appreciating that the contact stress and contact area are functions of placement pressure, stent geometry, and balloon compliance may help direct development of novel stent designs and stent-deployment protocols so as to minimize vascular injury during stenting and perhaps to optimize long-term outcomes.

Keywords: stent — restenosis — vascular injury — balloon — finite element analysis

 

 

Simulation of the structure-mechanical behaviour of a PWR coolant loop under extreme loads

T. Schimpfke, H. Grebner, A. Höfler

Gesellschaft für Anlagen-und Reaktorsicherheit (GRS) mbH, Schwertnergasse 1, D-50667 Köln, Germany

Nuclear Engineering and Design, 190:117-126, 1999

Abstract: It is possible to simulate the structure-mechanical behavior of a pressurized-water-reactor coolant loop due to the loading conditions of rare-event sequences in an integral manner, or under abandonment of idealized assumptions for component-related boundary conditions and with consideration of interactions. These event sequences can then be assessed with sufficient reliability regarding the integrity of the components. The methods and models can also be used for the safety-oriented optimization of accident management measures, especially with regard to the fulfillment of general protection goals and the reduction of structure-mechanical effects. In this connection, particular attention must be paid to dynamic load types.

Keywords: Accident prevention — Computer simulation — Cooling systems — Finite element method — Load testing — Mathematical models — Mechanical testing — Nuclear reactor accidents — Steam generators — Strain — Stress analysis — Structural analysis

 

 

A dynamic analysis procedure for concrete-faced rockfill dams subjected to strong seismic excitation

Nasim Uddin

Civil Engineering, University of Evansville, 1800 Lincoln Ave, Evansville, IN 47722, USA

Computers and Structures, 72:409-421, 1999

Abstract: There is presently little analytical and essentially no observational evidence on the behavior of the concrete-face of the very popular concrete-faced rockfill (CFR) dams during strong seismic shaking. The choice of slab thickness and steel reinforcement is based solely on precedent, with performance under static loads being the only design consideration. To fill this gap, a dynamic finite element (FE) procedure is presented to design the concrete-face slab which involves a realistic modeling for the embankment material, the face slab, and the slab-rockfill interface. A set of historic accelerograms, with peak ground accelerations (pga) of about 0.60 g, is used as excitation. Numerical results highlight key aspects of the seismic response of CFR dams with emphasis on the internal forces developing in the slab. It is shown that slab distress may be produced only from axial tensile forces, developing mainly due to the rocking component of dam deformation. For the 0.60 g shaking tensile stresses much higher than the likely tensile strength of concrete development in the slab. All analyses in this FE study are performed with the ADINA special interface elements to model the slip and Newmark's time-integration algorithm for a direct step-by-step solution.

Keywords:  Acceleration — Algorithms — Computer simulation — Concrete slabs — Deformation — Earthquake resistance — Finite element method — Seismic waves — Structural loads — Tensile strength — Tensile stress

 

 

Replacement of the feedwater piping system in the reactor building outside the containment at Philippsburg I nuclear power station

A. Kessler1, M. Labes2, B. Schwenk3

1 EBW Kraftwerke GmbH, Stuttgart, Germany
2 Power Generation Group (KWU) of Siemens AG, Offenbach, Germany
3 EBW Kraftwerke GmbH KKP, Philippsburg, Germany

Nuclear Engineering and Design,  193:255-264, 1999

Abstract:  At Philippsburg/Nuclear Power Station the replacement of the feedwater lines (WB35) from their point of entry into the reactor building up to the first external isolation valve of each line brought the quality level of the whole of the feedwater pipe system in the reactor building with basic safety requirements. The design of the new piping was based on a state-of-the-art concept in the mechanical and fluid-dynamics behavior. The extensive analyses focused on the optimization of the closing behavior of the third damped check valves and the integrity analysis of the RPV nozzle. The integrity analysis was performed on the basis of a postulated reliably detectable defect, using the plastic limit load method with the specified yield strength as yield stress. The planning period for preparation of the licensing and approval documents lasted approximately 30 months, following a preliminary concept phase. Replacement was performed in 43 days.

Keywords: Accident prevention — Fluid dynamics — Nozzles — Nuclear reactor licensing —  Nuclear reactors — Optimization — Piping systems — Pressure vessels — Structural analysis —  Valves (mechanical) — Yield stress

 

 

Wall stress and strain analysis using a three-dimensional thick-wall model with fluid-structure interactions for blood flow in carotid arteries with stenoses

D. Tang1, C.Yang2, Y. Huang1, D.N. Ku3

1 Mathematics Department, Worcester Polytechnic Institute, Worcester, MA, 01609, USA
2 Mathematics Department, Beijing Normal University, Beijing, People's Republic of China
3 Georgia Inst. of Tech., School of ME, Atlanta, GA 30332, USA

Computers and Structures, 72:341-356, 1999

Abstract: Wall mechanics and fluid-structure interactions play important roles in artery collapse and plaque cap rupture, which leads directly to heart attack and stroke. A three-dimensional thick-wall model with fluid-structure interactions was introduced and solved using ADINA to investigate the wall stress and strain distributions and flow properties of blood flow in carotid arteries with symmetric and asymmetric stenoses. The Navier-Stokes equations were used as the governing equations for the fluid. The tube wall was assumed to be hyperelastic, homogeneous, isotropic and incompressible. The Ogden material model was used for the tube wall. Experimental data for a silicone tube with a 78% stenosis by diameter was used to derive the stress-strain relationship for the material. Results obtained indicate that severe stenosis causes considerable compressive stress in the tube wall which may be related to plaque cap rupture. Stenosis severity and asymmetry have considerable influence on wall stress and strain distributions. Three-dimensional wall deformation, flow pressure, velocity and shear stress fields were investigated.

Keywords: Carotid artery — Ogden material model — Stenoses — Three dimensional thick wall model

 

 

Core melt down and vessel failure: a coupled problem

G. Duijvestijn, J. Birchley

Laboratory for Safety and Accident Research (LSU ), Paul Scherrer Institute, 5232 Villigen PSI, Switzerland

Nuclear Engineering and Design, 191:17-30, 1999

Abstract: Analyses of lower head failure have been performed for a variety of core slump scenarios that result from three contrasting reactor accident sequences in a PWR. The cases cover a range of thermalhydraulic conditions in the vessel and core debris characteristics. The results show lower head failure occurs at a time which depends on the internal thermal-hydraulic conditions and debris characteristics. Failure may be local or global and may be due to one or more of the following processes: creep; plasticity (including thermo-plasticity); and melt-through. At low to moderate pressure, creep damage accumulates over a wide area, leading to probable global failure. Local plastic deformation becomes increasingly important at higher pressures or following a pressure spike, with a possibility of local failure. Local melting can occur before failure if there is a large concentrated heat flux. A question of particular interest for future study is raised by the CORVIS experiments, namely that the deformation can cause a gap to open between the structure and debris crust and hence increase the thermal resistance. Modest estimates of the gap resistance show a significant delay in failure. A coupled treatment of the thermal and mechanical response is needed to assess the dynamic gap behaviour effectively.

Keywords: Creep — Failure analysis — Heat flux — Heat resistance — Hydraulics — Nuclear power plants — Plasticity — Pressure vessels — Pressurized water reactors

 

 

Analytical and computational approaches for some fluid-structure interaction analyses

X. Wang

Institute of Paper Science and Technology, 500 10th Street, N.W., Atlanta, GA 30318, USA

Computers and Structures,  72: 423-433, 1999

Abstract: In this paper, we present an analytical model to study the interaction between a slender structure and the surrounding incompressible viscous flows. The governing equations for the suspended structure are derived under small deformation assumptions and with the consideration of fluid pressures and frictional forces. We obtain the discretized equations using the standard linearization procedure and spatial finite difference schemes. It is shown that for both laminar and turbulent flow conditions, the results derived from analytical approaches match the solutions of the ADINA fluid-structure analysis. Of course when geometries of fluid domains are complex, it is necessary to use a general purpose computational software. We also point out that for specific problems, such as the dynamic stability analysis of the structure surrounded by pulsatile flows, there is still a need for analytical approaches.

Keywords: Computational fluid dynamics — Computer simulation — Finite difference method — Finite element method — Laminar flow — Linearization — Loads (forces) —  Pressure — Pulsatile flow — Turbulent flow — Viscous flow

 

 

A 3-D thin-wall model with fluid-structure interactions for blood flow in carotid arteries with symmetric and asymmetric stenoses

D. Tang1, C. Yang2, D.N. Ku3

1 Department of Mathematical Sciences, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609-2280, USA
2 Mathematics Department, Beijing Normal University, Beijing, People's Republic of China
3 Georgia Institute of Technology, School of ME, Atlanta, GA 30332, USA

Computers and Structures,  72:357-377, 1999

Abstract: Severe stenosis may lead to critical flow conditions related to artery collapse, plaque cap rupture which lead directly to stroke and heart attack. A three-dimensional (3D) thin-wall model with flow-structure interactions was introduced and solved using ADINA to investigate the wall deformation and flow properties of blood flow in carotid arteries with symmetric and asymmetric stenoses. The Navier-Stokes equations were used as the governing equations for the fluid. The tube wall was assumed to be hyperelastic, homogeneous, isotropic and incompressible. The nonlinear large strain Ogden material model was used for the wall with the elastic properties determined experimentally for a silicone tube with a 78% stenosis by diameter. The results revealed that the behaviors of the 3D flow pressure, velocity and shear stress fields are very different from those of 2D models. Stenosis severity and asymmetry have considerable effects on those critical flow conditions such as negative pressure and high shear stress were found which may be related to artery collapse and plaque rupture.

Keywords: Biology computing — blood vessels — deformation — finite element analysis —  haemodynamics — Navier-Stokes equations — pipe flow

 

 


Thermal analysis of automotive lamps using the ADINA-F coupled specular radiation and natural convection model

Moore, William I. (Guide Corp); Donovan, Eric S.; Powers, Christopher R. Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 17-30

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: ADINA R&D Inc. has developed a code which has the capability to perform coupled specular radiation and fluid flow analysis using a ray tracing method. The code has been applied to automotive lamp thermal analysis to accurately predict lamp surface temperatures resulting from radiation and natural convection heating. The results have been successfully correlated with empirical data using an infrared thermal imaging camera. The code predictions were consistently within ±10% of measurements. The code can be applied to large FEA models of unstructured three-dimensional meshes with four-node tetrahedral elements. The ADINA-F Computational Fluid Dynamics code can now be used to perform thermal validation of automotive lamps for a wide variety of large and complex lamp designs. This capability can significantly reduce design costs and expensive prototyping. (8 refs.)

Keywords:  Headlights  -  Thermoanalysis  -  Computational fluid dynamics  -  Heat radiation  -  Natural convection  -  Computer simulation  -  Finite element method  -  Ray tracing  -  Infrared imaging  -  Cameras

Secondary  Keywords:  Automotive lamps  -  Coupled specular radiation  -  Natural convection model

 


Advances in crush analysis

Bathe, Klaus-Jürgen (Massachusetts Inst of Technology); Walczak, Jan; Guillermin, Olivier; Bouzinov, Pavel A.; Chen, Heng-Yee Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 31-47

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: Advances in capabilities for the crush analysis of structures are presented. Such analyses are difficult to perform and require state-of-the-art analysis procedures: efficient and reliable shell elements, an effective and general contact algorithm, efficient procedures to calculate the element stresses in elasto-plasticity, the use of consistent tangent matrices, effective nonlinear incremental solution strategies and the efficient solution of the algebraic finite element equations. Moreover, the effectiveness of the complete analysis process can only be achieved by ensuring that each of the above solution procedures is in an effective manner integrated into a complete solution scheme. This paper focuses on the advances developed in ADINA and presents various analysis cases solved with the program. (13 refs.)

Keywords:  Structural analysis  -  Strength of materials  -  Algorithms  -  Stresses  -  Elastoplasticity  -  Finite element method  -  Differential equations  -  Computational fluid dynamics  -  Computer simulation

Secondary  Keywords:  Crush analysis  -  Shell elements  -  Algebraic finite element equations

 


Nonlinear axisymmetric model with fluid-wall interactions for steady viscous flow in stenotic elastic tubes

Tang, D. (Worcester Polytechnic Inst); Yang, J.; Yang, C.; Ku, D.N. Source: Journal of Biomechanical Engineering, Transactions of the ASME, v 121, n 5, Oct, 1999, p 494-501

ISSN: 0148-0731 CODEN: JBENDY

Publisher: American Society of Mechanical Engineers

Abstract: Arteries with high-grade stenoses may compress under physiologic conditions due to negative transmural pressure caused by high-velocity flow passing through the stenoses. To quantify the compressive conditions near the stenosis, a nonlinear axisymmetric model with fluid-wall interactions is introduced to simulate the viscous flow in a compliant stenotic tube. The nonlinear elastic properties of the tube (tube law) are measured experimentally, and used in the model. The model is solved using ADINA (Automatic Dynamic Incremental Nonlinear Analysis), which is a finite element package capable of solving problems with fluid-structure interactions. Our results indicate that severe stenoses cause critical flow conditions such as negative pressure and high and low shear stresses, which may be related to artery compression, plaque cap rupture, platelet activation, and thrombus formation. The pressure field near a stenosis has a complex pattern not seen in one-dimensional models. Negative transmural pressure as low as -24 mmHg for a 78 percent stenosis by diameter is observed at the throat of the stenosis for a downstream pressure of 30 mmHg. Maximum shear stress as high as 1860 dyn/cm2 occurs at the throat of the stenoses, while low shear stress with reversed direction is observed right distal to the stenosis. Compressive stresses are observed inside the tube wall. The maximal principal stress and hoop stress in the 78 percent stenosis are 80 percent higher than that from the 50 percent stenosis used in our simulation. Flow rates under different pressure drop conditions are calculated and compared with experimental measurements and reasonable agreement is found for the prebuckling stage. (47 refs.)

Keywords:  Hemodynamics  -  Blood vessels  -  Flow interactions  -  Physiological models  -  Finite element method  -  Mathematical models  -  Compressive stress  -  Pressure drop  -  Viscous flow  -  Shear stress  -  Elasticity

Secondary  Keywords:  Stenotic elastic tubes  -  Transmural pressure  -  Stenosis

 


Dynamic analysis procedure for concrete-faced rockfill dams subjected to strong seismic excitation

Uddin, Nasim (Univ of Evansville) Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 409-421

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: There is presently little analytical and essentially no observational evidence on the behavior of the concrete-face of the very popular concrete-faced rockfill (CFR) dams during strong seismic shaking. The choice of slab thickness and steel reinforcement is based solely on precedent, with performance under static loads being the only design consideration. To fill this gap, a dynamic finite element (FE) procedure is presented to design the concrete-face slab which involves a realistic modeling for the embankment material, the face slab, and the slab-rockfill interface. A set of historic accelerograms, with peak ground accelerations (pga) of about 0.60 g, is used as excitation. Numerical results highlight key aspects of the seismic response of CFR dams with emphasis on the internal forces developing in the slab. It is shown that slab distress may be produced only from axial tensile forces, developing mainly due to the rocking component of dam deformation. For the 0.60 g shaking tensile stresses much higher than the likely tensile strength of concrete development in the slab. All analyses in this FE study are performed with the ADINA special interface elements to model the slip and Newmark's time-integration algorithm for a direct step-by-step solution. (16 refs.)

Keywords:  Concrete dams  -  Earthquake resistance  -  Finite element method  -  Concrete slabs  -  Computer simulation  -  Acceleration  -  Tensile strength  -  Structural loads  -  Deformation  -  Tensile stress  -  Seismic waves  -  Algorithms

Secondary Keywords:  Concrete faced rockfill dams  -  Seismic excitation  -  Peak ground acceleration

 


Distribution of vehicular loads on bridge girders by the FEA using ADINA: modeling, simulation, and comparison

Chen, Yochia (Penn State at Harrisburg) Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 127-139

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: This paper discusses how a general finite element (FE) code, such as ADINA, can be used to effectively and efficiently model the bridge superstructure system subjected to moving traffic loads and further to predict the accurate lateral distribution of such live loads on bridge longitudinal girders. An input generator suited for the ADINA Program was developed to facilitate the preparation of the tedious FE data as required, especially the varying movable loads. FE modeling techniques and features using the family of ADINA programs are presented and discussed in detail. Live-load distribution factors derived from the FE method are compared with those obtained by the other methods. Advantages of the FE method are also highlighted. (6 refs.)

Keywords:  Beams and girders  -  Highway bridges  -  Bridge components  -  Dynamic loads  -  Finite element method  -  Computer simulation  -  Ground vehicles

Secondary

Keywords:  Bridge girders  -  Vehicular loads

 


Effect of hardening layers and technological lubricants on heat exchange between workpiece and die

Gierzynska-Dolna, Monika (Technical Univ of Czestochowa); Lacki, Piotr Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 165-175

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: In this paper the numerical analysis of influence of contact force on the heat transfer in a forging process is presented. The contact force distribution obtained from the simulation of the forging process is used to analyse the heat transfer between the workpiece and the tool. Experimental results of the influence of contact force on the heat flux between two contact surfaces are shown. The numerical analysis has been performed using the ADINA system. (8 refs.)

Keywords:  Dies  -  Heat transfer  -  Temperature distribution  -  Loads (forces)  -  Lubricants  -  Numerical analysis  -  Forging  -  Computer simulation  -  Finite element method  -  Heat flux  -  Heat transfer coefficients  -  Mathematical models

Secondary Keywords:  Hardening layers  -  Contact force

 


Finite element analysis for walking vibration problems for composite precast building floors using ADINA: modeling, simulation, and comparison

Chen, Yohchia (Penn State at Harrisburg) Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 109-126

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: Building floors made of precast double-tee (DT) concrete sections could experience annoying vibration problems due to people walking. From the viewpoint of structural design, the issue of floor vibration acceptability is also important in addition to the conventional strength/safety criterion. In this paper, ADINA-based finite element (FE) techniques are described and discussed in detail for rational analysis and assessment for a large composite floor system subjected to walking vibration. In particular, the techniques of the FE modeling and the consideration and simulation of dynamic loading are addressed. Advantages of using ADINA for vibration studies and recommendations for analysis and design are presented. (14 refs.)

Keywords:  Floors  -  Precast concrete  -  Finite element method  -  Computer simulation  -  Dynamic loads  -  Structural design  -  Strength of materials  -  Accident prevention

Secondary  Keywords:  Composite precast building floors  -  Walking vibration

 


Theoretical study on contact strength of gears with finite element method

Zhang, Wobo (Ji'nan Staff Univ of Science and Technology) Source: Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery, v 30, n 3, 1999, p 89-92 Language: Chinese

ISSN: 1000-1298 CODEN: NUYCA3

Abstract: In order to evaluate gear contact strength precisely, based on the gear generation theory with finite element method (FEM), this paper develops a tooth profile generation method and drive gear position formula. FEM model program including inter-outer meshing method and gear structure is also developed. The model date file used by ADINA analysis program is generated automatically and the gear contact strength is calculated with FEM model creation and ADINA analysis program. The calculated FEM result is compared with calculated result of traditional method and measured one, the results prove that FEM is much better than traditional method.


Blast analysis of complex structures using physics-based fast-running models

Bogosian, David D. (Karagozian & Case Structural Engineers); Dunn, Brian W.; Chrostowski, Jon D. Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 81-92

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: For situations requiring large numbers of parametric analyses, complex nonlinear models are too computationally intensive to be used. Instead, simplified engineering models (such as single degree of freedom) are often substituted, but at the risk of reduced fidelity in representing the response of the structure. In this paper, a hybrid method is presented whereby a complex ADINA model of a frame building is combined with a simplified engineering model to yield a physics-based fast-running model for computing the building's response to a range of blast loadings. This method allows realistic modeling of the load-deflection characteristics of each lateral load resisting frame (based on the nonlinear material properties and actual framing and bracing sizes and geometry) while running sufficiently quickly to allow analysis of numerous loading scenarios. The building analyzed is the Vertical Integration Building (VIB) at Cape Canaveral Air Station in Florida, a more than 200-foot high steel braced frame structure. Its analysis is part of ongoing range safety activities sponsored by the US Air Force 30th and 45th Space Wings, Safety Directorates. (6 refs.)

Keywords:  Buildings  -  Structural frames  -  Blast resistance  -  Computer simulation  -  Finite element method  -  Dynamic loads  -  Accident prevention  -  Mathematical models

Secondary  Keywords:  Physics based fast running model  -  Load deflection characteristics

 


Evaluation of a fully assembled armored vehicle hull-turret model using computational and experimental modal analyses

Gupta, A.D. (US Army Research Lab) Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 177-183

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: A three-dimensional finite element (FE) model of a multilayered hull-turret assembly of an armored vehicle was generated from major components such as the armored hull, turret and a 105 mm cannon models which were independently developed in PATRAN3 and assembled using rigid-link elements in the ADINA nonlinear dynamic FE code. Smaller components in the experimental vehicle were included as concentrated masses attached to specific sets of nodes in the hull corresponding to the actual locations of these components. Addition of these masses resulted in improved correlation between computational and experimental modal analyses. (6 refs.)

Keywords:  Warships  -  Computer simulation  -  Finite element method  -  Hulls (ship)  -  Dynamic response  -  Mathematical models  -  Dynamics

Secondary  Keywords:  Armored vehicle  -  Multilayered hull turret assembly

 


Contact analysis for drum brakes and disk brakes using ADINA

Hohmann, C. (Univ of Siegen); Schiffner, K.; Oerter, K.; Reese, H. Source: Computers and Structures, v 72, n 1-3, Jul-Aug, 1999, p 185-198

ISSN: 0045-7949 CODEN: CMSTCJ

Publisher: Elsevier Science Ltd

Abstract: Brakes in cars and trucks are safety parts. Requirements not only in performance but also in comfort, serviceability and working lifetime are high and rising. Optimal design of today's brake systems is found using additional calculations based on finite element methods. For both types of brake systems, drum brakes and disk brakes, the different parts of brakes, i.e. the brake pad with the friction material, the counter body and calliper, can be modelled. Two examples are given in this paper: a drum brake of a trailer and a typical disk brake used in passenger cars. The main problem to be solved is the calculation of the distribution of contact forces between brake pad and counter body (drum or disk). The contact problem includes friction and is solved using the ADINA 7.1 sparse solver. After the brake pressure is applied, the turning moment on the axle rises constantly until the drum or disk respectively changes from sticking to sliding condition. It is shown that the sparse solver is highly efficient for this sophisticated nonlinear problem. Results include deformation, stress distribution, contact pressure and showing which regions of the contact area are in sticking or sliding condition. (6 refs.)

Keywords:  Brakes  -  Friction  -  Finite element method  -  Computer simulation  -  Truck trailers  -  Automobiles  -  Pressure  -  Axles  -  Deformation  -  Stress concentration

Secondary Keywords:  Drum brakes  -  Disk brakes  -  Contact forces

 


What has the finite element method done for (or to) geotechnical engineering?

Christian, John T. (Stone & Webster Engineering) Source: Civil Engineering Practice, v 14, n 2, Autumn, 1999, p 73-74

ISSN: 0886-9685 CODEN: CIEPED

Publisher: Boston Society of Civil Engineers Section / ASCE

Abstract: There are several systems designed specifically for geotechnical engineering. The first group of such packages include PLAXYS, CRISP and SIGMA, as well as FLAC. These programs include features unique to the geotechnical needs. A second group of widely used programs consists of general purpose, nonlinear finite element systems such as ABAQUS, ANSYS, ADINA and SAP. While these programs were usually written for structural or mechanical applications, they permit the user to incorporate additional routines to deal with peculiarly geotechnical issues. Third, there are special purpose programs, such as those that handle dynamic problems or simulation of tied back excavations. (2 refs.)

Keywords:  Civil engineering  -  Geotechnical engineering  -  Finite element method  -  Software engineering

Secondary Keywords:  Software package PLAXYS  -  Software package CRISP  -  Software package SIGMA  -  Software package ABAQUS  -  Software package ANSYS  -  Software package ADINA  -  Software package SAP

 


Effective uses of finite element analysis in geotechnical engineering

Marr, W. Allen (GEOCOMP Corp) Source: Civil Engineering Practice, v 14, n 2, Autumn, 1999, p 89-98

ISSN: 0886-9685 CODEN: CIEPED

Publisher: Boston Society of Civil Engineers Section / ASCE

Abstract: Powerful microcomputers, easy-to-use interfaces, better software and more experienced engineers are making it cost effective to use finite element analysis on more routine work. Using a finite element program to analyze many geotechnical problems in a few hours from start to finish is now possible for experienced users. This optimistic statement assumes that the geometry is known and relatively simple, the material parameters are defined and the analyst is very familiar with the software being used. A strong understanding of effective stress principles and of soil behavior is essential to anyone doing finite element analysis of geotechnical problems for design.

Keywords:  Geotechnical engineering  -  Finite element method  -  Computer aided analysis  -  Soil mechanics  -  Stress analysis  -  Microcomputers  -  User interfaces

Secondary  Keywords:  Software package ADINA

 


Mechanics of airway narrowing and its role in the remodeling process in asthma

Kamm, Roger D. (Massachusetts Inst of Technology); Hrousis, Constantine A.; Ressler, Barbara; Lee, Richard T.; Drazen, Jeffrey M. Source: American Society of Mechanical Engineers, Bioengineering Division (Publication) BED, v 42, 1999, p 349-350

CODEN: ASMBEP ISBN-10: 0-7918-1611-7

Conference: 1999 Bioengineering Conference, Jun 16-Jun 20 1999, Big Sky, MT, USA Sponsor: ASME; AIChE; Biomedical Engineering Society; The United States National Committee on Biomechanics

Publisher: American Society of Mechanical Engineers

Abstract: The hypothesis relating to the alterations in mechanical stress associated with airway constriction is examined using two methods. Numerical simulations are performed of airways constricted by smooth muscle constriction. Cell culture experiments are used to examine the effect of the associated stresses on the expression of genes related to stress adaptation. (3 refs.)

Keywords:  Muscle  -  Biomechanics  -  Pulmonary diseases  -  Antigens  -  Computer simulation  -  Cells  -  Animal cell culture  -  Genes  -  Finite element method  -  Collagen  -  Growth kinetics

Secondary  Keywords:  Asthma  -  Smooth muscle constriction  -  Software Package ABAQUS  -  Software Package ADINA  -  Epithelial cells

 

A Dynamic Analysis Procedure For Concrete-Faced Rockfill Dams Subjected To Strong Seismic Excitation

Nasim Uddin

Civil Engineering, University of Evansville, 1800 Lincoln Ave, Evansville, IN 47722, USA

Computers and Structures, 72:409-421, 1999.

Abstract: There is presently little analytical and essentially no observational evidence on the behavior of the concrete-face of the very popular concrete-faced rockfill (CFR) dams during strong seismic shaking. The choice of slab thickness and steel reinforcement is based solely on precedent, with performance under static loads being the only design consideration. To fill this gap, a dynamic finite element (FE) procedure is presented to design the concrete-face slab which involves a realistic modeling for the embankment material, the face slab, and the slab-rockfill interface. A set of historic accelerograms, with peak ground accelerations (pga) of about 0.60 g, is used as excitation. Numerical results highlight key aspects of the seismic response of CFR dams with emphasis on the internal forces developing in the slab. It is shown that slab distress may be produced only from axial tensile forces, developing mainly due to the rocking component of dam deformation. For the 0.60 g shaking tensile stresses much higher than the likely tensile strength of concrete development in the slab. All analyses in this FE study are performed with the ADINA special interface elements to model the slip and Newmark's time-integration algorithm for a direct step-by-step solution.

 



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