Warp-knitted spacer fabrics are considered, which are plates or shells composed of two knitted plane layers connected by vertical beams. Our aim is to compute the effective stiffness and permeability of such spacer fabrics on the basis of their structure and properties of yarns and the monofil. In order to reduce the computational effort and simplify the computational model, homogenization and dimension reduction techniques are applied. They replace the fabric by an equivalent two-dimensional plate or shell with effective elastic properties. To compute the effective permeability, the fluid simulation is done on the fully resolved micro-structure. The paper demonstrates the algorithm on application examples. We compute the elastic properties of a spacer fabric and its effective permeability for different outer-plane compression stages. Numerical examples were performed by applying the multi-scale simulation tools, developed at Fraunhofer ITWM and by comparing with the corresponding experimental results, based on measurements performed at the TU Dresden. The developed algorithms and simulation tools enable a full virtualisation of the material design adapted to exposure scenarios in various technical application cases, i.e. infiltration processes with polymers in the field of fiber reinforced composites, which enables new discoveries for the designing and manufacturing process of 3D warp-knitted spacer fabrics.

考虑到经编间隔织物，它们是由垂直横梁连接的两个编织平面层组成的板或壳。我们的目的是根据纱线和单丝的结构和性能来计算此类间隔织物的有效刚度和渗透性。为了减少计算量并简化计算模型，应用了均化和降维技术。它们用具有有效弹性的等效二维板或外壳代替织物。为了计算有效渗透率，在完全解析的微结构上进行了流体模拟。本文在应用实例上演示了该算法。我们计算了间隔织物的弹性特性及其在不同外平面压缩阶段的有效渗透性。通过应用在Fraunhofer ITWM开发的多尺度模拟工具，并根据德累斯顿理工大学的测量结果，与相应的实验结果进行比较，得出了数值示例。先进的算法和仿真工具可对材料设计进行完全虚拟化，以适应各种技术应用案例中的暴露场景，即纤维增强复合材料领域的聚合物浸渗工艺，从而为3D经纱的设计和制造工艺带来新发现针织的间隔织物。