Modelling the geometry of the repeat unit cell of three-dimensional weave architectures

Analytical elastic stiffness model for 3D woven orthogonal interlock composites

“…The volume fraction (V o ) of a tow element is calculated from the characteristic dimensions of the tow and the unit cell that were predicted previously by the geometric model [18]. The V o of the tow is equal to the area fraction of the tow and is determined via equation 1.…”

“…Figure 2 illustrates the operation of the elastic stiffness model. Upon execution of elastic stiffness model the geometric properties originating from the results provided by the geometric modelling methodology [18] selects the unit cell to be discretised. The whole unit cell is representative of the macroscale i.e.…”

“…al. [18] describe the development of a geometric model that is capable of calculating the necessary inputs for the present elastic stiffness model. The geometric model and the present elastic stiffness model are driven by weaving parameters and the constituent material properties from the manufacturer's datasheet.…”

“…For instance Summerscales and Russell [19] found evidence that assuming the lenticular shape to be symmetrical is incorrect. However, one or more of these ideal tow cross sections is often adopted in models [18,[20][21][22] and have shown good agreement between calculated and measured values.…”

Multi-scale damage modelling of 3D woven composites under uni-axial tension

“…Since the 3D woven composite is generally constructed by repeating identical unit cells, its behaviour can be simulated by modelling a unit cell with periodical boundary conditions [1] . The unit cell is mostly modelled as a block with the tow following idealised [2] or realistic paths [3,4] and its constant [2] or variable [3,4] cross-section being elliptical [5,6,7], rectangular [6], or lenticular [7]. Once the unit cell is built, load or displacement is then applied to the unit cell and the behaviour can be then simulated using Finite Element Analysis or analytical methods.…”