Effect of compaction pressure on the thermal conductivity of UO2-BeO-Gd2O3 pellets
DOI:
https://doi.org/10.15392/bjrs.v9i2B.1474Palavras-chave:
thermal conductivity, nuclear fuel, uranium dioxide, beryllium oxide, gadolinium oxideResumo
The (U,Gd)O2 fuels are used in pressurized water reactors (PWR) to control the neutron population in the reactor during the early life with the purpose of extended fuel cycles and higher target burnups. Nevertheless, the incorporation of Gd2O3 in the UO2 fuel decreases the thermal conductivity, leading to premature fuel degradation. This is the reason for the addition of beryllium oxide (BeO), which has a high thermal conductivity and is chemically compatible with UO2. Pellets were obtained from powder mixtures of the UO2, Gd2O3 and BeO, being the oxide contents of the beryllium equal to 2 and 3wt%, and the gadolinium fixed at 6wt%. The pellets were compacted at 400, 500, 600, and 700 MPa and sintering under hydrogen reducing atmosphere. The purpose of this study was to investigate the effect of BeO, Gd2O3 and compaction pressure on the thermal conductivity of the UO2 pellets. The thermal diffusivity and conductivity of the pellets were determined from 298 K to 773 K and the results obtained were compared to UO2 fuel pellets. The thermal diffusivity was determined by Laser Flash and Thermal Quadrupole methods and the thermal conductivity was calculated from the product of thermal diffusivity, the specific heat capacity and density. The sintered density of the pellets was determined by the xylol penetration and immersion method. The results showed an increase in the thermal conductivity of the pellets with additions of BeO and with the compaction pressure compared to the values obtained with UO2 pellets.Downloads
Referências
IAEA - International Atomic Energy Agency. Thermophysical Properties Database of materials for light water reactors and heavy water reactor. IAEA TECDOC-1496, Vienna: IAEA, 2006. 397p.
SOLOMON A. A.; REVANKAR S.; McCOY J. K. Enhanced Thermal Conductivity Conductivity Oxide Fuels, Purdue University School of Nuclear Engineering. West Lafayette, Indiana, USA. 2006. Available at: <https://www.osti.gov/biblio/862369-iDA0bI/>. Last accessed: 21 May 2020.
BUCKLEY J.; TURNER J. D.; ABRAM T. J. Uranium Dioxide-Molybdenum Composite Fuel Pellets with enhanced Thermal Conductivity Manufactured Via Spark Plasma Sintering. J Nuclear Mat, v. 523, p. 360-368, 2019.
ISHIMOTO S.; HIRAI M.; ITO K.; KOREI Y. Thermal Conductivity of UO2-BeO Pellet. J Nuc Sci Tech, v. 33:2, p 134-140, 1996.
MASSIH A. R. Effects of Additives on Uranium Dioxide Behavior, Swedish Radiation Safety Authority. Uppsala, Sweden. 2014. Available at:
<https://www.stralsakerhetsmyndigheten.se/contentassets/af14180bb6a94795a26c233fd4351d7b/201421-effects-of-additives-on-uranium-dioxide-fuel-behavior> Last accessed: 21 May 2020.
McCOY K.; MAYS C. Enhanced Themal Conductivity Oxide Nuclear Fuels by Co-sintering with BeO: II. Fuel Perfomance and Neutronics. J Nuc Materials, v. 375, p. 157-167, 2008.
GARCIA C. B.; BRITTO R. A.; ORTEGA L. H.; MALONE J. P.; McDEAVITT S. M. Manufacture of a UO2-Based Nuclear Fuel with Improved Thermal Conductivity with the Addition of BeO. Met and Mat Transactions E, v. 76, p. 70-76, 2017.
HIRAI M. Thermal diffusivity of UO2-Gd2O3 Pellets, J Nuc Mat, v. 173, p. 247-254, 1990.
IWASAKI K. et al. Thermal Conductivity of Gd2O3-dispersed UO2 pellet, In: ATALANTE, 2008, Montpellier. Annals of Atalante 2008. Montpellier: French Alternative Energies and Atomic Energy Commission, 2008. Available at:
<https://inis.iaea.org/collection/NCLCollectionStore/_Public/40/034/40034680.pdf>
Last accessed: 21 May 2020.
CAMARANO D. M.; MANSUR F. A.; SANTOS A. M. M.; FERRAZ W. B.; FERREIRA R. A. N. Effects of Beryllium and Compaction Pressure on the Thermal Diffusivity of Uranium Dioxide Fuel Pellets. Int. J. Thermophys, v 38:137, 2017.
CAMARANO D. M.; MANSUR F. A.; SANTOS A. M. M.; FERRAZ W.B.; FERREIRA R. A. N. Thermal Conductivity and Thermal Diffusivity of UO2-BeO Nuclear Fuel Pellets”, In: INTERNATIONAL NUCLEAR ATLANTIC CONFERENCE, 2017, Belo Horizonte. Annals of INAC 2017. Belo Horizonte: Comissão Nacional de Energia Nuclear, 2017.
ASTM - American Society for Testing and Materials. Standard Test Method for Thermal Diffusivity by the Flash Method. ASTM E1461, West Conshohocken, Palo Alto: ASTM, 2013. 11p.
DEGIOVANNI A.; MAILLET D.; ANDRÉ S.; BATSALE J. C.; MOYNE C. Thermal Quadrupoles - Solving the Heat Equation Through Integral Transform, 1st ed. London: Wiley, 2000.
JCGM - Joint Committee for Guides in Metrology Evaluation of measurement data. Guide to the Expression of Uncertainty in Measurement. JCGM 100:2008, Sèvres, Paris: JCGM, 2008. 120p. Available at:
<https://www.bipm.org/utils/common/documents/jcgm/JCGM_100_2008_E.pdf>.
Last accessed: 21 May 2020.
ASTM - American Society for Testing and Materials. Standard Test Methods for Density of Compacted or Sintered Powder Metallurgy (PM) Products Using Archimedes’ Principle. ASTM B962, West Conshohocken, Palo Alto: ASTM, 2017. 7p.
IAEA - International Atomic Energy Agency. Thermo-physical Materials Properties Database. IAEA-THERPRO, Seoul: IAEA, 2010. Available at: <http://therpro.hanyang.ac.kr>. Last accessed: 21 May 2020.
IAEA - International Atomic Energy Agency. Thermophysical Properties of Materials for Nuclear Engineering: A Tutorial and Collection of Data. IAEA-THPH, Vienna: IAEA, 2008. 191p. Available at: <http://www-pub.iaea.org/MTCD/Publications/PDF/IAEA-THPH_web.pdf>. Last accessed: 21 May 2020.
Krishnan R. V.; PANNEERSELVAM G.; MANIKANDAN P.; ANTONY M. P.; NAGARAJAN K. Heat Capacity and Thermal Expansion of Uranium-Gadolinium Mixed Oxide. J Nuc Radiochem Sci, v. 10, p. 19-26, 2009.
Downloads
Publicado
Edição
Seção
Licença
Direitos autorais (c) 2021 Brazilian Journal of Radiation Sciences
Este trabalho está licenciado sob uma licença Creative Commons Attribution 4.0 International License.
Declaro que o presente artigo é original, não tendo sido submetido à publicação em qualquer outro periódico nacional ou internacional, quer seja em parte ou em sua totalidade. Declaro, ainda, que uma vez publicado na revista Brazilian Journal of Radiation Sciences, editada pela Sociedade Brasileira de Proteção Radiológica, o mesmo jamais será submetido por mim ou por qualquer um dos demais co-autores a qualquer outro periódico. Através deste instrumento, em meu nome e em nome dos demais co-autores, porventura existentes, cedo os direitos autorais do referido artigo à Sociedade Brasileira de Proteção Radiológica, que está autorizada a publicá-lo em meio impresso, digital, ou outro existente, sem retribuição financeira para os autores.
Licença
Os artigos do BJRS são licenciados sob uma Creative Commons Atribuição 4.0 Licença Internacional, que permite o uso, compartilhamento, adaptação, distribuição e reprodução em qualquer meio ou formato, desde que você dê o devido crédito ao (s) autor (es) original (is) e à fonte, forneça um link para a licença Creative Commons, e indique se mudanças foram feitas. As imagens ou outro material de terceiros neste artigo estão incluídos na licença Creative Commons do artigo, a menos que indicado de outra forma em uma linha de crédito para o material. Se o material não estiver incluído no licença Creative Commons do artigo e seu uso pretendido não é permitido por regulamentação legal ou excede o uso permitido, você precisará obter permissão diretamente do detentor dos direitos autorais. Para visualizar uma cópia desta licença, visite http://creativecommons.org/licenses/by/4.0/
