Abaqus

ABAQUS, description, 123 Accelerating-rate calorimetry advantages and disadvantages, 428-429 experimental procedure, 429-430 hazard evaluation on MDl, 43lr isothermal decomposition studies, 431-432,433/ use in assessment of hamrds of chemicals, 428... 

The basic scheme for the numerical solution is the same as that used for the 1 -D model, except that in this case the solid temperature field used to solve the DAE system for each monolith channel must be calculated from the three-dimensional solid-phase energy balance equation. The three-dimensional energy balance equation can be solved by a nonlinear finite element solver (such as ABAQUS) for the solid-phase temperature field while a nonlinear finite difference solver for the DAE system calculates the gas-phase temperature and... 

Many commercial finite element computer programs (for example ABAQUS, ADINA, ANSYS, DYNA, DYNA3D, LS-DYNA, NASTRAN and NONSAP) arc readily available for nonlinear dynamic analysis. Other computer codes, such as CBARCS, COSMOS/M, STABLE, ANSR 1 have been developed specifically for the design of structures to resist blast toads. All these computer programs possess nonlinear analysis capabilities to varying degrees. 

EPP foam inserts for bumpers (fenders) are a major application area (91) (98) (161) (279) (302) (362) (366) (386) (398) (424). Unlike EPS, EPP has the multiimpact performance required, can fit inside the hollow bumper beam, and has a low mass. ABAQUS FEA has been used (a.28) to design such inserts. Arange of cross-sectional shapes were considered in an attempt to achieve a near uniform crushing load of about 3 kN over a deflection of 50 mm. Those with triangular cut outs were found to be best. 

Stress calculations are carried out by the finite element method. Here, the commercial finite method code ABAQUS (Hibbit, Karlsson, and Sorensen, Inc.) is used. Other codes such as MARC, ANSYS are also available. To calculate the stresses precisely, appropriate meshes and elements have to be used. 2D and shell meshes are not enough to figure out stress states of SOFC cells precisely, and thus 3D meshes is suitable for the stress calculation. Since the division of a model into individual tetrahedral sometimes faces difficulties of visualization and could easily lead to errors in numbering, eight-comered brick elements are convenient for the use. The element type used for the stress simulation here is three-dimensional solid elements of an 8-node linear brick. In the coupled calculation between the thermo-fluid calculation and the stress calculation a same mesh model have to be used. Consequently same discrete 3D meshes used for the thermo-fluid analysis are employed for the stress calculation. Using ABAQUS, the deformations and stresses in a material under a load are calculated. Besides this treatment, the initial and final conditions of models can be set as the boundary conditions and the structural change can thus be treated. 

Thus Equation (10.33) is solved as the new equilibrium equation. To calculate the thermal expansion behavior of the model, the thermal expansion coefficient is necessary as the calculating parameter. If the temperature of the model is even, the initial temperature and the final temperature are used as just a calculating parameter. If a temperature distribution exists in the model, the temperature distribution data is dispensable for the stress calculation. The temperature is firstly calculated by a CFD and the calculated data is used as the boundary condition in the stress calculation. If the thermal expansion coefficient is temperature dependent, the temperature dependence must be considered in the calculation. Here the temperature data at the nodes is transferred from STAR-CD to the ABAQUS. 

Numerical calculations for the residual stresses in the anode-supported cells are carried out using ABAQUS. After modeling the geometry of the cell of the electro-lyte/anode bi-layer, the residual thermal stresses at room temperature are calculated. The cell model is divided into 10 by 10 meshes in the in-plane direction and 20 submeshes in the out-plane direction. In the calculation, it is assumed that both the electrolyte and anode are constrained each other below 1400°C and that the origin of the residual stresses in the cell is only due to the mismatch of TEC between the electrolyte and anode. The model geometry is 50 mm x 50 mm x 2 mm. The mechanical properties and cell size used for the stress calculation are listed in Table 10.5. 

Calculation of the deformation of the inter connector and internal stresses From the calculated temperature distributions, the deformation and related internal stresses of the interconnector are calculated using ABAQUS. 

The commercial finite element program, Abaqus [17], was used to calculate the stress distribution in an edge delamination sample. A fully three-dimensional model of the combinatorial edge delamination specimen was constructed for the finite element analyses (FEA). For clarity, some of the FEA results and schematics are presented as two-dimensional configurations in this paper (e.g.. Fig. 1). The film and substrate were assumed to be linearly elastic. The ratio of the film stiffness to the substrate stiffness was assumed to be 1/100 to reflect the relative rigidity of the substrate. This ratio also represents a typical organic... 

ABAQUS (2000). Finite Element Analysis Code and Theory (Standard and CAE),... 

In this study, residual thermal stresses were also eonsidered because co-cured lap joints generally undergo temperature drop (from 120D to 20D) during the curing process. The stress distributions in the co-cured single and double lap joints were analyzed using ABAQUS i.8 to be commercial finite element analysis software [21],... 

Use of Products), Vol. 15, American Society for Testing and Materials, Philadelphia, PA. (1998). ABAQUS/Standard User s Manual. Hibbitt, Karlsson Sorensen, Pawtucket. RI. Reddy, H. N. (1997). Mechanics of Laminated Composite Plates Theory and Analysis, CRC Press, Inc., Boca Raton, Florida. 

Some advanced general purpose finite-element codes, well adapted for stress analysis in particular, e.g. ABAQUS or MSC.MARC, have certain capabilities to simulate the stress-assisted diffusion, too. Unfortunately, they still are limited in some rather important aspects. As regards ABAQUS, this allows to perform simulations of the stress-assisted diffusion governed by equation (5) "over" the data of an accomplished solution of a geometrically and physically nonlinear stress-strain analysis, i.e., for the stationary stress field at the end of some preliminary loading trajectory, but not for the case of simultaneous transient loading and hydrogenation. 

Macroscopic phenomena are described by systems of integro-partial differential algebraic equations (IPDAEs) that are simulated by continuum methods such as finite difference, finite volume and finite element methods ([65] and references dted therein [66, 67]). The commonality of these methods is their use of a mesh or grid over the spatial dimensions [68-71]. Such methods form the basis of many common software packages such as Fluent for simulating fluid dynamics and ABAQUS for simulating solid mechanics problems. 

Figure 3 shows the axial temperature distributions of fluids under the normal operating condition. Temperature distribution in the ceramic block was analysed with ABAQUS Vcr.6.4. Figure 4 shows a computational grid of a 1/4 sector of the upper half part of the block. 

Numerical solutions are obtained using the ABAQUS code [2]. 

Hibbitt, Karlsson and Sorensen, Computer Code ABAQUS, Inc., Providence, RI, 1994... 

Four research teams—AECB, CLAY, KIPH and LBNL—studied the task with different computational models. The computer codes applied to the task were ROCMAS, FRACON, THAMES and ABAQUS-CLAY. All of them were based on the finite-element method (FEM). Figure 6 presents an overview of the geometry and the boundary conditions of respective models, including the nearfield rock, bentonite buffer, concrete lid, and heater. The LBNL model is the largest and explicitly includes nearby drifts as well as three main fractures... 

The AECL team used an in-house MOTIF finite-element code (Guvanasen and Chan 2000), which is based on an extension of the classical poroelastic theory of Biot (1941). This code has undergone extensive verification and validation (Chan et al. 2003). The CTH team employed the commercially available, general-purpose finite-element code ABAQUS/Standard 6.3 (ABAQUS manuals). This code adopts a macroscopic thermodynamic approach. The porous medium is considered as a multiphase material, and an effective stress principle is used to describe its behaviour. ABAQUS allows the value of bulk modulus of the mineral grains as an input parameter. In order to select an appropriate value for this low-permeability, low-porosity rock, the CTH team compared the ABACjus solution with Biot s (1941) analytical solution for ID consolidation in the form presented by Chan et al. 2003). 

In general, the head and displacement results from the two teams are in better agreement than the Darcy velocity and effective stress results. This is not surprising. Head and displacement are primary unknown variables calculated by both MOTIF and ABAQUS, whereas Darcy velocity and stress are derivatives so that any inaccuracies arising from the extremely high material property contrast between the rock matrix and the fracture zones would be accentuated. 

ABAQUS/Standard User s Manual Version 6.3. ABAQUS, Inc. ... 

Calculated using MOTIF (AECL) and ABAQUS (CTH) in a Fracture Zone (Point I) and in the Repository zone (4). 

Pure Spot FSW. Awang et al. (Ref 23) presented some results on finite element modeling of FSSW using ABAQUS/Explicit (ABAQUS, Inc.) as a finite element solver. A three-dimensional (3-D) coupled thermal-stress model was used to calculate the thermomechanical response of the FSSW process. Adaptive meshing and advection schemes, which make it possible to maintain mesh quality under large deformations, were used to simulate the material flow and temperature distribution in the FSSW process. 

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