Abstract
Because boiling water reactors use control blades during operation, there can be significant changes to the local axial power shape, coolant density profile, and other parameters when the blades are inserted. Previous work examined the reactor operating parameters that impact cask reactivity. These previous studies identified limiting conditions for fuel cask reactivity or the direction of trends with cask reactivity (e.g., lower coolant densities result in higher cask reactivity). However, using limiting conditions for all parameters simultaneously is unrealistic. When the control blades are inserted deeply into the reactor—a limiting condition—the power is reduced and the void fraction decreases—a less limiting condition. This paper identifies the impacts of using assembly-specific conditions for control blade history, coolant density profile, burnup profile, and fuel temperature profile. Results indicate that cask reactivity is reduced when using assembly-specific operating conditions versus combining limiting conditions for the individual parameters of interest. The magnitude of reactivity reduction for using assembly-specific conditions varies based on each assembly and its operating conditions.
| Original language | English |
|---|---|
| Title of host publication | ANS NCSD - 2017 Nuclear Criticality Safety Division Topical Meeting |
| Subtitle of host publication | Criticality Safety - Pushing Boundaries by Modernizing and Integrating Data, Methods, and Regulations |
| Publisher | American Nuclear Society |
| ISBN (Electronic) | 9780894487408 |
| State | Published - 2017 |
| Event | 2017 Nuclear Criticality Safety Division Topical Meeting: Criticality Safety - Pushing Boundaries by Modernizing and Integrating Data, Methods, and Regulations, NCSD 2017 - Carlsbad, United States Duration: Sep 10 2017 → Sep 15 2017 |
Publication series
| Name | ANS NCSD - 2017 Nuclear Criticality Safety Division Topical Meeting: Criticality Safety - Pushing Boundaries by Modernizing and Integrating Data, Methods, and Regulations |
|---|---|
| Volume | 2017-September |
Conference
| Conference | 2017 Nuclear Criticality Safety Division Topical Meeting: Criticality Safety - Pushing Boundaries by Modernizing and Integrating Data, Methods, and Regulations, NCSD 2017 |
|---|---|
| Country/Territory | United States |
| City | Carlsbad |
| Period | 09/10/17 → 09/15/17 |
Funding
*This manuscript has been authored by U-BattTelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energ. TheyUnited States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energ.gov/ydownloads/doe-public-access-plan). This work was provided by the US Nuclear Regulatory Commission (NRC). The authors would like to thank the NRC staff for their helpful comments and their support of this work. Special thanks are extended to Justin Clarity and Ugur Mertyurek from Oak Ridge National Laboratory for reviewing this paper and providing valuable suggestions, and Rose B. Raney for editing the document.
Keywords
- Boiling water reactor
- Burnup credit
- Correlated conditions