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Słowa kluczowe:
Finite element analysis, Thermodynamics, Material‐deforming processes

Streszczenie:
This paper deals with the evaluation of the effects of initial stresses developed during the pressurized casting process. The stresses are induced by the external pressure applied to the cast and developed due to thermal loading. The effect of the stresses is considered as a second order effect by means of investigating the influence of the ‘geometric’ or ‘initial stresses’ stiffness matrix on the response of the cast. The problem formulation is done in the updated Lagrangian (UL) frame. An implicit time integration scheme is applied to solve the transient thermomechanical problem in a staggered form. The constitutive mechanical model is elasto-viscoplastic with hardening incorporated with a Mises yield function. The finite element method is employed and a few 3D numerical examples are presented.

Słowa kluczowe:
Squeeze casting, Initial stresses, Coupled problems, Finite elements

Streszczenie:
The paper deals with an overview of some industrial applications leading to a formulation for advanced numerical techniques. The applications comprise squeeze casting processes, forming of tablets and petroleum reservoir modelling. All of the problems lead to solutions of highly nonlinear, coupled sets of multiphysics equations.

Słowa kluczowe:
squeeze forming, powder compaction, oil fields, coupled problems, thermomechanics, porous media, fluid flow, nonlinear solid mechanics, phase transformations, microstructural solidification models, numerical methods, contact problems, discrete elements, finite elements.

Streszczenie:
In order to guarantee the strength and thus the quality of the tablets produced during the tabletting process, it is essential to understand the deforming characteristics of excipient binders. The present numerical work is motivated to provide an insight into the mechanical behaviour of the particle deformation of the excipient binder. In the present study pregelatinised starch is selected, which is known to behave in a ductile manner during compaction. An elasto-viscoplastic material model has been selected in the present study to simulate the deformation behaviour of the pregelatinised starch. Elasto-viscoplastic model 1S chosen because all the plastic deformation exhibits rate-dependency to some extent, and it is a well-developed model for simulating non-linear deformation which has been studied for four decades (Perzyna (1966), Zabaras and Arif (l992)).

Słowa kluczowe:
discrete element method, finite element method, viscoplasticity, adaptive meshing

Streszczenie:
During mould filling due to decreasing of liquidus temperature takes place solidification pocess. The paper deals mostly with a presentation of an application of a microstructural solidification model. The Navier Stokes equation describing the flow problem is solved using Taylor Galerkin method.

Słowa kluczowe:
mould filling, microstructural solidification, thermomechanics

Streszczenie:
The presented paper deals with the design sensitivity of a sequentially coupled thermo-mechanical problem. The key finding is to provide a tool for optimisation software (analytical design sensitivity gradients) for a sequentially coupled thermal-mechanical problem.

Słowa kluczowe:
casting process, thermomechanics, parameter sensitivity analysis