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Title: A semi-empirical model for the formation and depletion of the high burnup structure in UO 2

Abstract

In the rim zone of UO 2 nuclear fuel pellets, the combination of high burnup and low temperature drives a microstructural change, leading to the formation of the high burnup structure (HBS). In this work, we propose a semi-empirical model to describe the formation of the HBS, which embraces the polygonisation/recrystallization process and the depletion of intra-granular fission gas, describing them as inherently related. To this end, we per-formed grain-size measurements on samples at radial positions in which the restructuring was incomplete. Moreover, based on these new experimental data, we assume an exponential reduction of the average grain size with local effective burnup, paired with a simultaneous depletion of intra-granular fission gas driven by diffusion. The comparison with currently used models indicates the applicability of the herein developed model within integral fuel performance codes.

Authors:
ORCiD logo [1];  [2];  [3];  [4];  [5];  [5]
  1. European Commission, Karlsruhe (Germany). Joint Research Centre; Department of Energy, Milan (Italy)
  2. European Commission, Karlsruhe (Germany). Joint Research Centre; Technical Univ. of Munich (Germany)
  3. Department of Energy, Milan (Italy)
  4. Idaho National Lab. (INL), Idaho Falls, ID (United States)
  5. European Commission, Karlsruhe (Germany). Joint Research Centre
Publication Date:
Research Org.:
Idaho National Lab. (INL), Idaho Falls, ID (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1393171
Report Number(s):
INL/JOU-16-39368
Journal ID: ISSN 0022-3115; PII: S0022311516307279
Grant/Contract Number:
AC07-05ID14517
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 487; Journal Issue: C; Journal ID: ISSN 0022-3115
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; fuel performance; grain size measurement; high burnup structure

Citation Formats

Pizzocri, D., Cappia, F., Luzzi, L., Pastore, G., Rondinella, V. V., and Van Uffelen, P.. A semi-empirical model for the formation and depletion of the high burnup structure in UO 2. United States: N. p., 2017. Web. doi:10.1016/j.jnucmat.2017.01.053.
Pizzocri, D., Cappia, F., Luzzi, L., Pastore, G., Rondinella, V. V., & Van Uffelen, P.. A semi-empirical model for the formation and depletion of the high burnup structure in UO 2. United States. doi:10.1016/j.jnucmat.2017.01.053.
Pizzocri, D., Cappia, F., Luzzi, L., Pastore, G., Rondinella, V. V., and Van Uffelen, P.. Tue . "A semi-empirical model for the formation and depletion of the high burnup structure in UO 2". United States. doi:10.1016/j.jnucmat.2017.01.053. https://www.osti.gov/servlets/purl/1393171.
@article{osti_1393171,
title = {A semi-empirical model for the formation and depletion of the high burnup structure in UO 2},
author = {Pizzocri, D. and Cappia, F. and Luzzi, L. and Pastore, G. and Rondinella, V. V. and Van Uffelen, P.},
abstractNote = {In the rim zone of UO2 nuclear fuel pellets, the combination of high burnup and low temperature drives a microstructural change, leading to the formation of the high burnup structure (HBS). In this work, we propose a semi-empirical model to describe the formation of the HBS, which embraces the polygonisation/recrystallization process and the depletion of intra-granular fission gas, describing them as inherently related. To this end, we per-formed grain-size measurements on samples at radial positions in which the restructuring was incomplete. Moreover, based on these new experimental data, we assume an exponential reduction of the average grain size with local effective burnup, paired with a simultaneous depletion of intra-granular fission gas driven by diffusion. The comparison with currently used models indicates the applicability of the herein developed model within integral fuel performance codes.},
doi = {10.1016/j.jnucmat.2017.01.053},
journal = {Journal of Nuclear Materials},
number = C,
volume = 487,
place = {United States},
year = {Tue Jan 31 00:00:00 EST 2017},
month = {Tue Jan 31 00:00:00 EST 2017}
}

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