Computer finite-element mesh

The finite element mesh used in the computations is shown in the top of Figure 5.6. Similar to the RTM process dP/dn is set to zero on all solid boundaries and the pressure is... 

A number of one dimensional computer models have been developed to analyze thermionic converters. These numerical models solve the nonlinear differential equations for the thermionic plasma either by setting up a finite element mesh or by propagating across the plasma and iterating until the boundary conditions are matched on both sides. The second of these approaches is used in an analytical model developed at Rasor Associates. A highly refined "shooting technique" computer program, known as IMD-4 is used to calculate converter characteristics with the model ( ). 

Peskin [49] used the Galerkin finite-element method to compute current distribution and shape change for electrodeposition into rectangular cavities. A concentration-dependent overpotential expression including both forward and reserve rate terms was used, and a stagnant diffusion layer was assumed. An adaptive finite-element meshing scheme was used to redefine the problem geometry after each time step. 

To proceed with simulations of stress-assisted diffusion with rather modest computational facilities available, it turned out to be indeed necessary to reduce the FEM-problem size. Among two possible approaches, i.e., coarsening of the mesh of the modelled "full-scale" specimen or shrinking the domain of diffusion simulation focusing on the locations of prospective hydrogen assisted fracture initiation near the notch, the second one seems to be preferable. The relevant data about stress fields may be transferred to this domain from the full scale mechanical analyses, performing their interpolation for the finite element mesh for diffusion, if convenient. 

Figure 3. Finite element mesh and computed velocity field for 4 1 entry flow.

Fig. 13 Computational model for U-Profile die design (A) preland, die land, and free surface as computational domain (B) finite element mesh (symmetry exploited to reduce computational requirements) (C) boundary conditions for simulation of polymer fiow through die and extrudate free surface and (D) relevant profiles (1) preland inlet (2) die land (uniform along flow length) (3) final free surface (target extrudate profile) and (4) symmetry plane.

Fig. 3.7. Finite element mesh used to compute the eigenstates of the quantum corral (courtesy of Harley Johnson).

Fig. 10.37. Outcome of numerical calculation of the energy minimizers associated with martensite (adapted from Lnskrn (1996)) (a) an example of a finite element mesh used to model the martensitic micro structure, (h)-(d) the results of microstructure computations using different levels of mesh refinement.

The conceptual features of the model are illustrated in fig. 12.18. The basic idea is the simultaneous use of two computational meshes to treat the same overall spatial domain. As shown in the top frame of fig. 12.18, a finite element mesh... 

Strains and stresses were computed for the joined specimen cooled uniformly to room temperature from an assumed stress-free elevated temperature using numerical models described in detail previously [19, 20]. The coordinate system and an example of the finite element mesh utilized are shown in Figure 3. Elastie-plastic response was permitted in both the Ni and Al203-Ni composite materials a von Mises yield condition and isotropic hardening were assumed. 

Cortis CM, Friesner RA. Numerical solution of the Poisson-Boltzmann equation using tetrahedral finite-element meshes. J Comput Chem 1997 18 1591-1608. 

Subdividing the body to be computed into finite elements results in a mesh composed of numerous single elements. A set of linear differential equation represents the complete finite element mesh of the modeled piezoelectric substrate. 

Bechet, E., Cuilliere, J.-C., and Trochu, F. Generation of a Finite Element MESH from Stereolithography (STL) Files, Computer-Aided Design, vol. 34, no. 1 (2002) pp. 1-17. 

This computational imbalance motivated development of the Plastic Domain Decomposition (PDD) method described in this paper. Developed PDD is applied to a large scale seismic soil-foundation-structure (SFS) interaction problem for bridge systems. It is important to note that the detailed analysis of seismic SFSI described in this paper is made possible with the development of PDD as the modeling requirements (finite element mesh size) were such that sequential simulations were out of questions. 

Computer analysis of crack propagation through finite element grids was developed by several authors. Cracks are represented by discontinuities of the finite element mesh, and smeared crack models were also applied. Cement-based matrices were considered as linear elastic bodies up to the point where cracks open and later their behaviour becomes highly non-linear. Various methods are applied to represent non-linear and heterogeneous materials and to simulate their behaviour under load (cf. Petersson 1981). In discrete models, cracks are represented as discontinuities in the finite element mesh. This is also where smeared crack models are introduced. 

Figure 10-18. A finite-element mesh applied to the ignition computer housing shown in Figure 10-13 and 10-14.

Figures 5.6 and 5.7 show 3D and 2D finite element mesh generation schemes of a prestressed concrete vessel designed for a high-temperature gas-cooled reaetor. Both internal and external loads have been computed in accordance with the method given in Chapter 3. The program CREEP, which...

---