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Impact Factor (2025): 6.9
DOI Prefix: 10.47001/IRJIET
Impact Factor (2025): 6.9
DOI Prefix: 10.47001/IRJIET
Vol 10 No 6 (2026): Volume 10, Issue 6, June 2026 | Pages: 26-32
International Research Journal of Innovations in Engineering and Technology
OPEN ACCESS | Research Article | Published Date: 05-06-2026
Using techniques method of lines (MOL) and finite difference (FD) methods to solve the neutron diffusion equations (NDE). In this work, a new strategy was proposed to compute the neutron flux, concentration, and temperature properties of thermal nuclear reactors. This approach holds the potential for developing the static diffusion equation for different grades of temperature. Finite difference method was used to convert the parabolic partial differential equations into ordinary differential ones. The converted equations were generalized to consider three different geometries namely: spherical, cylindrical, and Cartesian. Moreover, MOL was used to solve the time-dependent NDE with space-time terms which describe the dynamics of one and two-groups. Results of the study showed that the thermal diffusion properties of moderating materials for H2O found that the diffusion coefficient (D), diffusion length (L) and Albedo β(∞) were 0.142 cm, 2.88 cm, and 0.82, respectively. While the same diffusion properties for heavy water (D2O) were D=0.8 cm, L=100.0 cm, and β(∞)=0.968. Meanwhile, D=0.903 cm, L=50.0 cm, and β(∞)=0.930 for Graphite (14C). The generated results are compatible with other different methods of calculations. This study recommends using the MOL to solve the NDE as it gives more accurate results and practically efficient for thermal neutron reactors.
Neutron diffusion equations, Method of lines, Finite difference methods, Neutron flux, Thermal nuclear reactors.
Elsadig Omer Faduil, & Ebtisam Abdalla Yousif. (2026). Thermal Diffusion Properties of Moderating Materials H2O dnd D2O in Thermal Nuclear Reactors. International Research Journal of Innovations in Engineering and Technology - IRJIET, 10(6), 26-32. Article DOI https://doi.org/10.47001/IRJIET/2026.106002
This work is licensed under Creative common Attribution Non Commercial 4.0 Internation Licence
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