Finite element code

Another alternative for such problems that has become widely available in Lagrangian finite element codes is the eroding slide line option (see, e.g., [66]). 

This paper will discuss the formulation of the simulator for the filament winding process which describes the temperature and extent of cure in a cross-section of a composite part. The model consists of two parts the kinetic model to predict the curing kinetics of the polymeric system and the heat transfer model which incorporates the kinetic model. A Galerkin finite element code was written to solve the specially and time dependent system. The program was implemented on a microcomputer to minimize computer costs. 

Versatile Finite Element Code for Polymer and Composite Processing... 

Curing of Polyimlde Resin. Thermoset processing involves a large number of simultaneous and interacting phenomena, notably transient and coupled heat and mass transfer. This makes an empirical approach to process optimization difficult. For instance, it is often difficult to ascertain the time at which pressure should be applied to consolidate the laminate. If the pressure is applied too early, the low resin viscosity will lead to excessive bleed and flash. But if the pressure is applied too late, the diluent vapor pressure will be too high or the resin molecular mobility too low to prevent void formation. This example will outline the utility of our finite element code in providing an analytical model for these cure processes. 

The examples outlined above are intended to show the utility of a generalized computer model for polymer processing problems. Such a model is able to adapt itself to a wide variety of situations simply by adjustments to the input dataset, rather than requiring alterations to the code itself. This flexibility makes the code somewhat more difficult to learn initially, but this might be minimized by embedding the finite-element code itself in a more "user-friendly" graphics-oriented shell. 

Due to difficulty in implementing FEMs, commercial software packages like Comsol Multiphysics are often used, since they allow the application of these methods without implementing an in-house finite element code. Specific details of the working and potentialities of Comsol Multiphysics can be found in the programme manuals [6, 7],... 

The thermal stresses were computed by the finite element code ANSYS [29], taking full advantage of the axial symmetry of the filter see Fig. 16. Both the temperature-dependent physical properties of the EX-54 filter (Section V) and the time-dependent thermocouple data were used as inputs to stress analysis. The maximum stresses in the axial and tangential directions at the midsection are summarized in Table 14. It should be noted in Table 14 that the radial temperature gradient is the major contributor to thermal stresses those due to axial gradient are less than 20%. 

Finite element analysis was carried out to study the validity of the evaluation formula derived in the previous section. The MMD specimen was discretized with 2-dimensional plane strain or 3-dimensional solid elements according to the purpose of the analysis, as shown in Fig. 4. The finite element code, MARC 2001, was used for the analysis. 

Industrial electrochemical cells, for which the local current distribution must be precisely determined, mainly involve multidimensional approaches. The electrokinetic problem is then solved using specific finite element codes such as COMSOL or Flux-Expert . 

Current density, eqn. (1), is calculated by the finite-element code Flux-Expert solving the Laplace equation for potential, eqn. (2) throughout the computational domain. 

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. 

Equation (21-132) provides only an approximate relation for determining stress distribution during compaction. With modern finite element codes based on soils and plasticity models of powder behavior... 

Computationally less demanding mean-field methods provide a tool to account for the out-of-plane constraints, but have the disadvantage of using phase averaged stress and stain fields. In the present work, an incremental Mori Tanaka approach is employed, which is implemented as a constitutive material law in a finite element code. Both two-dimensional and three-dimensional investigations are performed and the results are compared to the predictions of the extended unit cell approaches. 

The Tensile Stress Field, The main tool used in industry to assess the structural integrity of the propellant grain is a commercially available finite-element code that solves problems of finite elastic deformations. From numerical investigation performed with the code, one of the maximum strain locations (the critical point) is identified. This point (M) is located at the surface of the combustion chamber near the middle of the symmetry axis. 

The problem of high water resistivity is overcome by means of advanced commercial corrosimeters and computer aided design of the probes, thanks to the availability of finite element codes. The electric problems, such as streaming potentials and... 

Development of robust explicit finite element codes that can reliably accommodate contact between surfaces and time dependence. 

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