Projects per year
Abstract
The P1 approximation is a computationally efficient model for thermal radiation. Here, we present a P1 formulation in the context of the combined computational fluid dynamics and discrete element method (CFD-DEM), including closures for dependent scattering and coarse-graining. Using available analytical and semi-analytical solutions, we find agreement for steady-state and transient quantities in size-disperse systems. Heat flux is identified as the most sensitive quantity to predict, displaying unphysical spatial oscillations. These oscillations are due to a temperature slip at the locations of abrupt change in solid fraction. We propose two techniques that mitigate this effect: smoothing of the radiative properties, and pseudo-scattering. Furthermore, using up to a million times enlarged particles, we demonstrate practically limitless compatibility with coarse-graining. Finally, we compare predictions made with our code to experimental data for a pebble bed under vacuum conditions, and in presence of nitrogen. We find that a carefully calibrated simulation can replicate trends observed in experiments, with relative temperature error of less than 10%.
Original language | English |
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Pages (from-to) | 25-47 |
Number of pages | 23 |
Journal | Particuology |
Volume | 82 |
Early online date | 1 Feb 2023 |
DOIs | |
Publication status | Published - Nov 2023 |
Keywords
- CFD-DEM
- Coarse-graining
- P1
- Pebble bed nuclear reactor
- Thermal radiation
ASJC Scopus subject areas
- General Chemical Engineering
- Chemical Engineering(all)
- Materials Science(all)
Fields of Expertise
- Information, Communication & Computing
- Mobility & Production
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Dive into the research topics of 'Predictions of the P1 approximation for radiative heat transfer in heterogeneous granular media'. Together they form a unique fingerprint.Projects
- 1 Finished
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EU - MatheGram - Multiscale Analysis of Thermomechanical Behaviour of Granular Materials
Khinast, J., Radl, S. & Dhakal, R.
1/01/19 → 30/06/23
Project: Research project