The Generate Nonwoven Digital Twin app creates a Statistical Digital Twin of a non-woven micro-structure, resembling defined stochastic geometrical properties of the original. Ensure to have a representative cutout of your original structure, since otherwise the resulting twin structure cannot match all properties sufficiently. The app optimizes for curvature and, if selected, for density distribution in Z-direction

A result file (*.gdr) from FiberFind - Identify Fibers (AI) is required as input, providing necessary information for the target structure.

Clicking Edit opens the GeoApp - Generate Nonwoven Digital Twin dialog.

Enter a Result File Name and Browse for the Input Identify Fibers Result generated with FiberFind - Identify Fibers (AI).

The Downsampling factor determines the downsampling for the optimization to reduce runtime. The numbers of voxels in Z-direction must be dividable by this value. A higher value leads to a faster optimization, but reduces the accuracy. The final digital twin has the same resolution as the original structure.

Check Optimize Z Density Distribution if also the density distribution in Z-direction should be optimized. For this option a MatDict license is required. If selected, browse for an Thickness Estimation result file computed for the same structure as used for the Identify Fibers result.

The statistical digital twin is optimized using a differential evolution method. This optimization method mutates a population of nonwoven structures iteratively trying to improve them in every evolution to match the Identify Fibers result (and the 1D statistics result, if selected) finding a statistical digital twin.

Three iteration parameters can be edited. First, define the Population Size (PS) for one evolution. Then, set the Global Iterations (GI) of one differential evolution. For the local optimizer then set the number of Local Iterations (LI). The total number of iterations for the global optimizer is PS x GI x LI.

Clicking Run starts the twin generation.

Results

The result file is opened in the Result Viewer when the generation is finished, and the Report tab provides information about the structure generation and the resulting twin structure can be viewed in GeoDict. The algorithm optimizes for curvature and, if selected, for density distribution in Z-direction. In the Plots subtab of the Results tab find the convergence plots for the different parameters to optimize.

In the result folder find the intermediate results for the different optimization targets, created with FiberGeo.

The resulting twin structure is the Structure.gdt file. Additionally, the according FiberGeo result file Result.gdr can be opened in GeoDict, e.g. to view the input parameters.