2.5D woven shallow cross bending composites have been widely used in aerospace structures due to the excellent mechanical properties and structural integrity. Correctly characterizing the fiber structure with extrusion or deflection deformation is the key to study the materials properties in the micro- and meso-scale. Digital element method is an effective way to simulate the internal fiber bundle shape of the woven composites, however the obtained results depend on the selection of the simulation parameters. Based on the Micro-CT observation of 2.5D woven shallow cross bending SiO2f/ SiO2 composites, the digital element finite element model of the materials is established by using Abaqus software. The temperature load and boundary constraints are applied to simulate the fabric defor-mation process, and the digital element characteristic information after fabric deformation is extracted. Combined with the central path and cross-section shape discretization algorithm of fiber bundle, the structural shape of fiber bundle is obtained. By analyzing the influences of the selected element type, the elastic properties of the digital element, the number of elements and the friction coefficient on the simulation results, the main selecting principles of the simulation parameters are determined. The geometric model that can reflect the yarn deformation character-istics of the woven composites is obtained, which is consistent with the CT observation results. This method is uni-versal and can guide the digital element modelling of similar fabric composites.
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