Speaker
Description
Numerical modelling of thermography experiments traditionally relies on finite-element and heat-transfer simulations to predict temperature fields and defect signatures. However, the subsequent image formation process—governed by surface emissivity, reflection, transmission, viewing geometry and spectral camera response—is often treated only approximately. In this work we present a complementary approach in which physics-based rendering in Blender is used as a radiometric layer on top of thermal simulations, enabling realistic LWIR image formation from known temperature distributions.
The proposed workflow combines wavelength-dependent complex refractive indices with Planck-based emission in a unified Fresnel framework to model reflection, transmission, absorption and self-emission within a standard 3D rendering environment. Finite-element or analytical thermal models provide temperature fields, while Blender handles geometry, material optics, camera configuration and band integration. This separation allows the physical heat-transfer problem and the radiometric imaging problem to be treated consistently but independently.
Several representative case studies are presented, including angular emissivity effects on curved objects, imaging through infrared windows, reflection-dominated metallic scenes and active thermography of layered samples. These examples demonstrate how physics-based rendering complements FEM-based thermal modelling by revealing radiometric artefacts, angular biases and spectral effects that strongly influence measured thermograms.
The proposed framework provides a practical digital-twin approach for thermography experiment design, interpretation and algorithm validation, bridging thermal simulation and realistic infrared image formation.
