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Introduction

Quick Overview

Getting started

Release Notes

Geometry Simplification

Geometry Simplification

Preparing CAD Geometry for FEM

Creating effective virtual thermal sensors begins with properly prepared 3D CAD models and mesh data. This guide covers essential practices for optimizing your geometry for thermal finite element modeling.

Introduction

The Twin Fabrica offers two approaches for preparing your geometry:

  • Import a STEP file and prepare the mesh directly within the software (suitable for simple geometries)
  • Import a mesh file and start right away with model generation (suitable for complex geometries)

This guide will focus on key principles to follow regardless of which approach you choose.

Key Recommendations

Remove Small and Irrelevant Details

  • Delete small features that don't significantly affect thermal properties
  • Focus on thermally relevant components
  • Example: Small bolts or tiny geometric details can be removed

Simplify Complex Geometries

  • Replace complex shapes with simpler ones while maintaining overall volume
  • Preserve thermal relevance in simplified models
  • Use Boolean operations to combine or subtract volumes

Address Problematic Areas

Intersecting Volumes

  • Remove or simplify complex intersections where different materials meet
  • These can lead to meshing errors and worsen overall mesh quality

Interface Volumes

  • Be cautious with areas where small volumes meet large surfaces
  • These can create mesh density issues and increase node count unnecessarily

Conformal Meshes

  • Aim for meshes where nodes at shared faces are shared
  • Avoid disproportionate elements or abruptly ending nodes
  • Conformal meshes ensure better simulation accuracy and stability

Mesh Requirements

To work properly with Twin Fabrica, ensure your mesh has the following properties:

  1. Conformal mesh - Nodes at shared faces must be shared
  2. First-order elements - Use linear elements rather than higher-order ones
  3. Tetrahedral elements - The mesh must consist of tetrahedra

Benefits of Conformal Meshes

Conformal meshes provide several advantages:

  • Easier Preprocessing: No interfaces or connections between mesh zones to manage
  • Improved Numerical Efficiency: Eliminates data transfer between zones, leading to more efficient calculations
  • Increased Accuracy: Ensures smooth transitions, preserving solution accuracy
  • Avoids Sudden Mesh Size Changes: Maintains integrity of solution and reduces numerical errors

Iterative Approach to Geometry Preparation

  1. Start with broad simplifications
  2. Test mesh generation
  3. Identify problematic areas
  4. Further refine based on feedback
  5. Repeat until suitable mesh quality is achieved

Important Note

This approach is suitable for simple geometries. For complex geometries with many entities and contact surfaces, importing a pre-prepared mesh file is recommended.