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arXiv · 2501.17087

Multiscale simulations of three-dimensional nanotube networks: Enhanced modeling using unit cells

Fabian Gumpert·Dominik Eitel·Olaf Kottas·Uta Helbig·Jan Lohbreier
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Abstract

This study presents a simulation approach for three-dimensional nanotube networks using cubic and tetragonal unit cells to enhance modeling efficiency. A random-walk algorithm was developed to generate these networks, which were analyzed in a Finite Element Method (FEM) simulation to assess their electrical conductivity. The percolation probability as a function of the nanotube filling factor can be derived from these simulation results. It is found that smaller tetragonal unit cells can replicate the behavior of larger networks with significantly reduced computational effort, achieving a 20 times reduction in computational time while receiving similar results. In this work, we focus on carbon-doped titanate nanotubes for hydrogen applications, but the method is adaptable for other nanocomposite applications. The findings provide a universal framework for the investigation of nanotube-based materials.

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Fabian Gumpert, Dominik Eitel, Olaf Kottas, Uta Helbig, Jan Lohbreier. 2025-01-28. Multiscale simulations of three-dimensional nanotube networks: Enhanced modeling using unit cells. https://arxiv.org/abs/2501.17087

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