RadEx Simulator

A 3D thermal radiation exchange simulator for engineering applications

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Overview

RadEx Simulator is a desktop application for simulating transient thermal radiation exchange between two 3D objects.
The application follows a pipeline-driven engineering workflow, allowing users to import geometry, define physical properties, and analyze heat exchange over time through an intuitive GUI.

This project is developed as a portfolio project demonstrating skills in scientific computing, geometry processing, and GUI development.

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Mathematical Background

The simulation engine solves the Stefan-Boltzmann radiation law discretized over the surface triangles of the generated meshes.

1. Radiative Heat Transfer Rate

The net rate of heat transfer $Q$ between two surfaces is determined by:

$$Q_{1 \to 2} = \sigma \cdot \epsilon_{eff} \cdot A_1 \cdot F_{1 \to 2} \cdot (T_1^4 - T_2^4)$$

Where:

• $\sigma$: Stefan-Boltzmann constant ($5.6703 \times 10^{-8} , W \cdot m^{-2} \cdot K^{-4}$)
• $\epsilon_{eff}$: Effective emissivity
• $A_1$: Surface area of the emitting element
• $F_{1 \to 2}$: The geometric View Factor
• $T$: Absolute temperature in Kelvin

2. Discrete View Factor Calculation

To handle complex geometries, we calculate the view factor by summing the interaction between every surface triangle (facet) of Body A and Body B. For any two facets $i$ and $j$:

$$dF_{ij} = \frac{\cos(\theta_i) \cos(\theta_j)}{\pi s^2} A_j$$

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Key Features

• Import and visualize STL geometries for two independent objects
• Interactive 3D positioning and inspection
• Tetrahedral mesh generation per object
• Surface-based radiative view factor computation
• Definition of thermal parameters:
  • Emissivity
  • Initial temperature
  • Heat capacity
  • Thermal conductivity
• Transient thermal simulation with configurable time step and duration
• Clean, pipeline-oriented user interface

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Simulation Pipeline

1. Geometry Upload
   Load STL files for two bodies.

2. Positioning
   Translate and orient objects in 3D space while preventing overlap.

3. Meshing
   Generate tetrahedral meshes for each object.

4. Materials
   Assign radiative and thermal properties.

5. Simulation
   Compute transient radiative heat exchange.

6. Results
   Analyze and visualize temperature evolution.

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Technologies Used

• Python 3
• PySide6 / Qt Designer – GUI development
• VTK – 3D visualization and interaction
• STL & mesh processing libraries
• Qt Stylesheets (QSS) – UI styling

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Status

🚧 Work in progress

Planned improvements:

• Internal heat conduction modeling
• Support for more than two bodies
• Material property database
• Export of results (CSV, plots, images)

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Motivation

The goal of this project is to combine engineering simulation methods with modern desktop UI development, focusing on modular design, usability, and visualization quality.
It is intended as a demonstration of skills relevant to simulation software development and scientific visualization.

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License

This project is provided for educational and portfolio purposes.