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performance of finished FDM parts [40]. This implies that determination of the build
strategy will have a pronounced effect on the properties and ultimately the
performance of the finished product. Dimensional stability, resulting from process-
related thermal stresses and the interactions of different parts of the built shape
would also be influenced by the deposition strategies. Possible influences of the
curved layer deposition on the mechanical behaviour of a simple thin shell type part
are investigated in the current research. Part geometry, finite element modelling
strategies and results are presented in the following sections
5.2 Solid modelling of flat and curved layer FDM parts
The part selected for the finite element simulation of the curved layer and flat layer
fused deposition is the same simple thin shell type part used in the experimental
analysis presented in Chapter 4. The solid model of the part is reproduced in Fig. 5.1
for the sake of continuity.
Fig. 5.1 Thin shell-type part considered for the FEA
Creation of the solid model and conversion of the same into a finite element mesh for
the consideration of the boundary conditions would have been relatively simple and
straightforward, had the material structure been continuous and homogeneous.
However, the material structure in FDM parts is inferior due to the porosity generated
from an insufficient fusing of adjacent roads and layers. The overall properties of the
prototype can be modelled by the lamination theory, at the macro level. At the micro
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