Thermal Transport in Off‐Stoichiometric Uranium Dioxide by Atomic Level Simulation

Watanabe, Taku; Srivilliputhur, Srinivasan; Schelling, Patrick K.; Tulenko, J.S.; Sinnott, Susan B.; Phillpot, Simon R.

doi:10.1111/j.1551-2916.2009.02966.x

Cited by 50 publications

(32 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…14 The typical grain size of UO 2 in pristine nuclear reactor fuel is ~20 mm; by contrast MD simulations indicated that there is only a significant effect on the thermal conductivity for grain sizes of ~600 nm or less. 14 However, this study did not address the issue of the effects of grain boundary segregation on thermal transport which could be significant.…”

Section: Our Previous MD Simulations Havementioning

confidence: 97%

“…12 They showed that all of these potentials are limited to some degree or another in the fidelity with which they reproduce the physical properties of UO 2 . The thermaltransport properties as described by one such potential, that of Busker et al, 13,14 has been examined in detail. This potential was chosen because it is also parameterized for hypo-and hyperstoichiometric UO 2 , which most of the other potentials were not.…”

Section: Thermal Transport: Microstructure Scalementioning

confidence: 99%

See 1 more Smart Citation

Thermal conductivity of UO2 fuel: Predicting fuel performance from simulation

Phillpot

El–Azab²,

Chernatynskiy

et al. 2011

JOM

Self Cite

View full text Add to dashboard Cite

How would you……describe the overall significance of this paper? Atomistic level simulations have not traditionally contributed to nuclear fuel performance simulations. However, recent advances in methodologies and computer power are now enabling atomic level simulations to provide mechanistic insights and parameters that can help in the development of performance codes.…describe this work to a materials science and engineering professional with no experience in your technical specialty? Predicting the thermal and mechanical properties of nuclear fuel is a difficult task due to the many length and time scales involved. In this paper we discuss how the results obtained at the atomistic scale contribute to the continuum models of the standard nuclear fuel performance codes.…describe this work to a layperson? Nuclear reactor performance depends crucially on the ability of the nuclear fuel to transport energy generated by the nuclear reaction to the electricity generating station. This ability is influenced greatly by the structure of the fuel at the very fine scale: down to the position of the individual atoms. In this paper we discuss how computer simulations are able to penetrate to this scale and help to predict energy transport characteristics of the nuclear fuel.Recent progress in understanding the thermal-transport properties of UO 2 for fission reactors is reviewed from the perspective of computer simulations. A path to incorporating more accurate materials models into fuel performance codes is outlined. In particular, it is argued that a judiciously integrated program of atomic-level simulations and mesoscale simulations offers the possibility of both better predicting the thermal-transport properties of UO 2 in light-water reactors and enabling the assessment of the thermal performances of novel fuel systems for which extensive experimental databases are not available.

show abstract

Section: Our Previous MD Simulations Havementioning

confidence: 97%

Section: Thermal Transport: Microstructure Scalementioning

confidence: 99%

Thermal conductivity of UO2 fuel: Predicting fuel performance from simulation

Phillpot

El–Azab²,

Chernatynskiy

et al. 2011

JOM

Self Cite

View full text Add to dashboard Cite

show abstract

“…41 While these irradiation conditions do not necessarily reflect the reactor conditions, they were tailored to capture relevant physical mechanisms important for validation of thermal transport models. 43,44 It should be noted that the original intention was to study all of these conditions in UO 2 , but has not yet been accomplished due to difficulties that was encountered in performing ion irradiations on UO 2 over a broad range of temperatures and ion fluences that produced samples suitable for TR measurements.…”

Section: Measurements In Ion Irradiated Materialsmentioning

confidence: 99%

“…19 In addition to the fission gases, the effect of nonstoichiometry and Frenkel pairs on thermal conductivity is also important. 43,69 These types of defects may exist under the presence of radiation flux and are absent in standard post irradiation examination.…”

Section: Importance Of Irradiation Damage On Thermal Conductivitymentioning

confidence: 99%

Investigation of thermal transport in composites and ion beam irradiated materials for nuclear energy applications

et al. 2016

View full text Add to dashboard Cite

Thermal transport in materials used for energy applications is a physical process directly tied to performance and reliability. As a result, a great deal of effort has been devoted to understanding thermal transport in materials whose ability to conduct heat is critical. Here, our objective is to discuss the utility of laser-based thermoreflectance (TR) approaches that provide microscale measurement of thermal transport. We provide several examples that implement the TR technique to investigate thermal transport in materials used in nuclear energy applications. First, we discuss utility of this technique to measure thermal conductivity in ion irradiated ceramic materials during investigations where the primary objective is to understand the impact of radiation induced crystalline structure defects on thermal transport. We also present the capability of TR approach to resolve thermal conductivity of each layer in tristructural isotropic fuel, silicon carbide fiber composites, and 2nd phase precipitates in uranium silicide. Finally, the ability to measure interface thermal resistance between adjacent layers in composites is demonstrated.

show abstract

“…Several examples have been published recently. Molecular dynamics computations were applied for extracting the thermal expansion and thermal conductivity of un-irradiated UO2 fuel and implementing the correlation in the FRAPCON code [1]. A similar molecular dynamics analysis was carried out to simulate the interaction of a He or Xe filled bubble with a fission fragment [2], or empirical potential simulations were applied in order to predict swelling due to soluble solid fission in a fuel performance code [3].…”

Section: Introductionmentioning

confidence: 99%