GeoDict LamiGeo GeoApp — Laminated Composite Modeling

LamiGeo is a GeoDict application developed for the parametric generation of multi‑layer continuous fiber‑reinforced composite structures. Using a unified interface, users can define the number of layers, individual layer thicknesses, fiber angles per layer, fiber and matrix materials, fiber diameter, fiber solid volume fraction, fiber overlap and isolation distance, fiber waviness, and coating regions around fiber layers. LamiGeo automatically converts these parameters into detailed 3D voxel microstructures and connects with ElastoDict for further analysis of effective stiffness, stress‑strain distribution, nonlinear deformation, damage, and failure. By rapidly changing layup and microstructural parameters, researchers and engineers can compare multiple laminate designs before physical sample preparation, understand the relationship between structural parameters and material properties, and provide a digital foundation for the development of lightweight, high‑stiffness, and high‑strength composites.

1. Parametric 3D Modeling of Multi‑Layer Fiber‑Reinforced Laminates

The performance of multi‑layer fiber‑reinforced laminated materials depends not only on the fibers and matrix, but also on the number of plies, individual layer thickness, fiber orientation, fiber volume fraction, and interlayer structure. LamiGeo automatically generates customizable multi‑layer fiber‑reinforced composite laminates. Users can define the number of layers, layup angles, fiber diameter, fiber volume fraction, fiber waviness, coating regions, and fiber spacing to quickly build 3D voxel models suitable for digital experiments.

Traditional laminate design is usually described in terms of layup angles, ply thickness, and material parameters—for example: 0° unidirectional layers, 90° transverse layers, +45° and −45° angled layers, symmetric laminates, cross‑ply laminates, and quasi‑isotropic laminates. Such ply descriptions can describe the macroscopic composition of a laminate, but cannot directly show the fiber arrangement, fiber spacing, local waviness, or the true spatial relationship between fibers and matrix within each layer. Based on user‑defined layup parameters, LamiGeo generates fibers with specified orientations in each layer and combines multiple layers into a complete 3D laminate structure. The final model is represented in voxel form, distinguishing different material phases such as fibers, matrix, and optional coating regions, providing a geometric foundation for subsequent micromechanical simulations.

2. Key Features of LamiGeo

Customizable Layer Count and Layup Angles – Users can set the number of layers and assign individual fiber orientations to each layer. Layup configurations may include 0°/90° cross‑ply, +45°/−45° angle‑ply, combinations of 0°, 90° and ±45°, multi‑layer structures with repeated orientations in different sequences, and symmetric or asymmetric layups.

Layer Thickness Control – Through the Fiber Layer Height parameter, users can set the thickness of each fiber layer. Layers may have uniform thickness or different thicknesses according to design requirements, enabling structures such as equal‑thickness multi‑layer laminates, laminates with varying thickness combinations, structures with different surface and core layer thicknesses, and localized reinforcing or functional layers.

Fiber Diameter and Fiber Volume Fraction – Users can specify fiber diameter and fiber solid volume percentage within each layer. Changing these parameters allows the creation of digital laminates with different fiber contents and packing densities for comparing microstructural and performance differences.

Fiber and Matrix Material Selection – LamiGeo allows users to select both matrix and fiber materials from GeoDict's extensive material library. Typical combinations include E‑glass fiber with epoxy, carbon fiber with epoxy, and other fiber‑reinforced polymer systems. In subsequent ElastoDict calculations, different material phases can be assigned elastic, plastic, damage, or failure properties.

Non‑Overlapping Fiber Generation – LamiGeo can generate fibers that do not overlap each other. Users can also set an isolation distance to control the minimum spacing between fibers. This feature is suitable for building physically separated continuous fiber structures, avoiding unrealistic fiber interpenetration in digital models.

Fiber Waviness – Actual laminated composites may exhibit some degree of fiber waviness or deviation from ideal orientation due to manufacturing, placement, and curing processes. LamiGeo uses the Fiber Waviness parameter to describe angular variations around the fiber direction. This allows comparison between ideal straight fibers, fibers with slight waviness, and laminates with different degrees of waviness, making digital models more representative of real geometries.

Fiber Layer Coating – Users can set a coating region around fibers in the Z‑direction. This parameter can create additional material zones above and below the fiber layer with specified thickness, enabling models to represent more complex fiber layer structures.

3. Main Input Parameters

Key parameters in LamiGeo include: Result File Name, Voxel Length (spatial resolution), Domain Width in X‑ and Y‑direction, Number of Layers, Matrix Material, Fiber Material, No Fiber Overlap (overlap elimination), Isolation Distance, Fiber Layer Height, Fiber Layer Coating, Fiber Diameter, Fiber Solid Volume Percentage, Fiber Waviness, and Fiber Angles for each layer. After completing the settings, users input the fiber angles for each layer, and LamiGeo generates the laminate structure. The result file automatically opens in the GeoDict Result Viewer with a structure generation report.

4. Laminate Structure Examples

Example 1: Glass Fiber‑Epoxy Laminate – Parameters include E‑glass fiber (5 layers), epoxy matrix, fiber diameter 10 µm, layer thickness 300 µm, and layup pattern [0/90/±45/0/90]s. This example demonstrates a multi‑directional glass fiber composite.

Example 2: Carbon Fiber‑Epoxy Laminate – Parameters include 10 carbon fiber layers, epoxy matrix, fiber diameter 6 µm, layer thickness 300 µm, and layup pattern [0/0/0/±45/90]s. This model contains multiple 0° layers combined with ±45° and 90° layers, suitable for studying the relationship between primary load‑bearing direction reinforcement and multi‑directional response.

5. Digital Modeling Workflow

A typical LamiGeo workflow proceeds as follows: Define the computation domain (voxel size, X‑ and Y‑direction width, number of layers, and layer thicknesses). Select the constituent materials (fiber and matrix). Define fiber geometry (diameter, volume fraction, overlap allowance, isolation distance, waviness, and coating). Enter layup angles for each layer. LamiGeo automatically generates the 3D structure using FiberGeo's fiber generation capabilities. The resulting model can then be used for visualization, structural inspection, effective stiffness computation, stress‑strain and displacement field analysis, tensile or compressive deformation simulations, and damage and failure studies.

6. Relationship with FiberGeo

Running LamiGeo requires a FiberGeo license. FiberGeo is GeoDict's fiber structure modeling module for generating 3D digital fiber materials based on fiber shape, diameter, length, curvature, and orientation distribution. Its applications include laminates, short and long fiber composites, nonwovens, filter media, insulation materials, and gas diffusion layers. FiberGeo supports straight and curved fibers, different cross‑sectional shapes, random orientation distributions, and overlapping or non‑overlapping fiber placement. LamiGeo builds on these capabilities to provide a simplified and automated layup modeling workflow for multi‑layer fiber composites.

7. Connection with ElastoDict for Mechanical Property Prediction

ElastoDict is a module frequently used together with LamiGeo. LamiGeo generates the 3D laminated microstructure, while ElastoDict computes mechanical properties directly on the voxel structure without requiring conventional complex mesh generation. ElastoDict can predict the full effective stiffness tensor, local stress fields, local strain fields, displacement fields, and the orthotropic, transversely isotropic, or isotropic characteristics of the material. This allows users to compare the effects of different layup sequences, fiber volume fractions, and fiber orientations on macroscopic stiffness. The Deformations functionality in ElastoDict can simulate tension, compression, shear, cyclic loading, and large deformation. Constituent materials can be assigned elastic, plastic, viscoplastic, damage, and failure models, with outputs including stress‑strain curves and locations of damage initiation and final failure. Compared to using only macroscopic equivalent parameters, simulations based on LamiGeo microstructures can reveal which fiber layers carry the primary load, stress redistribution across different plies, localized high‑stress regions in the matrix, the influence of fiber waviness on stiffness and failure, and interactions between different material layers.

8. Value of Digital Layup Studies

LamiGeo enables rapid comparison of multiple layup designs without physical sample preparation. Users can independently vary the number of layers, layer thickness, fiber orientation, fiber diameter, fiber volume fraction, fiber spacing, and fiber waviness to identify which structural parameters have the greatest impact on target properties. Digital simulations provide not only overall stiffness but also local stress, strain, and damage evolution within fibers, matrix, and individual plies—information that is difficult to measure experimentally. By first screening layup schemes in virtual models, subsequent physical testing can be focused on the most promising designs.

9. Typical Application Areas

LamiGeo is suitable for composite R&D requiring continuous fiber multi‑layer structures, including: carbon fiber‑reinforced epoxy laminates, glass fiber‑reinforced polymer laminates, multi‑directional continuous fiber composites, hybrid fiber laminates, aerospace lightweight structures, automotive composite components, wind turbine blades and mechanical engineering components, protective equipment and sporting goods, and structural materials with directional stiffness requirements. GeoDict's composite solutions also support microstructure analysis, pore and defect identification, permeability prediction, stiffness tensor computation, and nonlinear mechanical simulation including damage and failure.

10. Required GeoDict Modules

Running the LamiGeo GeoApp requires a FiberGeo license for generating fibers in each layer and building the complete laminate structure. Depending on the application, ElastoDict is commonly used for mechanical property simulation, and additional modules such as ImportGeo‑Vol, PoroDict, MatDict, and ConductoDict may be employed for image import, pore analysis, material characterization, and conductivity prediction.