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A macroscopic thermal finite element analysis modeling platform for laser-based additive manufacturing is presented and validated. Its key characteristics include highly automated creation of simulation scenarios and increased computational efficiency. An investigation is carried out proving thermal shells a viable alternative to traditional solid elements, for building smaller and faster models. Full parameterization allows for rapid creation of specific modeling instances/scenarios. The use of shell elements, combined with model reduction techniques and advanced solver technology, result in very significantly reduced simulation times, compared to conventional modeling methods. Validation of the presented platform is carried out by comparison to results from other numerical models as well as experiments identified in the literature. Very good agreement for a wide range of materials and process parameters attest to its accuracy and universal application. This platform is the necessary basis for an Integrated Multiscale Modeling framework for systematically studying thermal patterns thereby ultimately increasing the scope of simulation to complete layers and whole parts.

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Drying of ceramic parts with complex geometry has been studied with emphasis on the effects of shrinkage on their final dimensions. The first step was to understand the processes governing moisture loss from a porous medium through experimental measurements yielding the coefficient of moisture expansion. As a result, non-homogeneous dimensional changes (shrinkage) occur in three-dimensional artefacts with varying cross-section. The moisture diffusion problem governed by Fick's laws was solved numerically by analogy to the heat conduction problem. To this end the correspondence was established between physical parameters, variables and boundary conditions of heat flow and diffusion, characteristically the coefficient of moisture expansion being analogous to the coefficient of thermal expansion. The numerical model established and solved using finite element analysis predicted moisture distribution inside the part as well as the resulting change in its shape. Validation of numerical predictions was first ensured in two dimensions by modelling a simple slab and comparing with experimental measurements. Validation for a fully three-dimensional shape required use of the wellestablished iterative closest point algorithm for surface point matching and subsequently the creation of an error map. The reverse of this numerical model was used to predict the appropriate die geometry starting with the shape of the desired part by taking into account the variable drying shrinkage allowance, and the relevant steps are outlined.