Thermal Conductivity of UO2–BeO–Gd2O3 Nuclear Fuel Pellets

• Published in: International journal of thermophysics Vol. 40; no. 12; pp. 1 - 9
• Main Authors: Camarano, D. M., Mansur, F. A., Santos, A. M. M., Ribeiro, L. S., Santos, A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2019; Springer Nature B.V
• Subjects: Beryllium oxide; Classical Mechanics; Condensed Matter Physics; Diffusivity; Gadolinium; Gadolinium oxide; Gadolinium oxides; Geophysics; Heat conductivity; Heat transfer; Industrial Chemistry/Chemical Engineering; Nuclear fuels; Pellets; Physical Chemistry; Physics; Physics and Astronomy; Quadrupoles; Room temperature; Tempmeko 2019; TEMPMEKO 2019: Selected Papers of the 14th International Symposium on Temperature and Thermal Measurements in Industry and Science; Theoretical density; Thermal conductivity; Thermal diffusivity; Thermodynamics; Uranium; Uranium dioxide; Beryllium oxide; Laser flash method; Nuclear fuel pellets; Thermal conductivity; Thermal diffusivity; Uranium dioxide; Thermal quadrupole method; Gadolinium oxide
• ISSN: 0195-928X; 1572-9567
• DOI: 10.1007/s10765-019-2574-5

In the present paper, the influence of the beryllium oxide addition to increase the thermal conductivity in uranium dioxide fuel pellets containing gadolinium oxide as burnable poison was investigated. Fuel pellets of UO 2 , UO 2 –BeO–Gd 2 O 3 , and UO 2 –Gd 2 O 3 were obtained in concentrations of 2–3 wt % of BeO and 6 wt % of Gd 2 O 3 . The thermal diffusivity was determined at room temperature and until 773 K by Laser Flash and Thermal Quadrupole methods, respectively. The thermal diffusivity and thermal conductivity were normalized to 95  % TD (theoretical density). The maximum relative expanded uncertainties of the thermal diffusivity and thermal conductivity measurements were estimated to be 7.5  % and 8.0  %, respectively. In addition, the obtained results were compared with the theoretical models and experimental data given in the literature. The results showed an increase in the thermal diffusivity and conductivity of the UO 2 pellets with additions of BeO as compared to the values obtained with UO 2 and UO 2 –Gd 2 O 3 pellets.