Effect of bi-directional excitation input on boiling water reactor scrammability
When a large earthquake occurs, a boiling water reactor is automatically shutdown through the insertion of control rods among fuel assemblies. A fuel assembly can vibrate in-plane when two seismic waves act on it in directions at right angles to each other in a horizontal plane. Although the state o...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | Japanese |
| Published: |
The Japan Society of Mechanical Engineers
2020-09-01
|
| Series: | Nihon Kikai Gakkai ronbunshu |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/transjsme/86/889/86_20-00227/_pdf/-char/en |
| _version_ | 1811220915346735104 |
|---|---|
| author | Yoshihiro GOTO Yuichi KOIDE Hirokuni ISHIGAKI Yugo HYOTANI |
| author_facet | Yoshihiro GOTO Yuichi KOIDE Hirokuni ISHIGAKI Yugo HYOTANI |
| author_sort | Yoshihiro GOTO |
| collection | DOAJ |
| description | When a large earthquake occurs, a boiling water reactor is automatically shutdown through the insertion of control rods among fuel assemblies. A fuel assembly can vibrate in-plane when two seismic waves act on it in directions at right angles to each other in a horizontal plane. Although the state of contact between a control rod and fuel assembly is different from that with one directional input, the effect of the difference on scram time is not clear. In this study, we evaluated control rod insertability under bi-directional excitation inputs using a dynamic insertion model of control rod. Sine waves were used as input waves, and their frequency corresponds to the first natural frequency of a fuel assembly. By changing the amplitude and phase difference of the input wave, we simulated the behaviors of the fuel assembly, such as vibration direction and whirling under bi-directional excitation inputs. As a result, we concluded that a comparatively long scram time was obtained when the fuel assembly vibrated in the direction orthogonal to the surface of the control rod blade. Additionally, as the phase difference between two horizontal inputs increased, there was increase in the scram time because the number of contacts between the control rod and the fuel assembly increased. |
| first_indexed | 2024-04-12T07:51:16Z |
| format | Article |
| id | doaj.art-7692f7425cbc49358aea4990ece5d2a9 |
| institution | Directory Open Access Journal |
| issn | 2187-9761 |
| language | Japanese |
| last_indexed | 2024-04-12T07:51:16Z |
| publishDate | 2020-09-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Nihon Kikai Gakkai ronbunshu |
| spelling | doaj.art-7692f7425cbc49358aea4990ece5d2a92022-12-22T03:41:36ZjpnThe Japan Society of Mechanical EngineersNihon Kikai Gakkai ronbunshu2187-97612020-09-018688920-0022720-0022710.1299/transjsme.20-00227transjsmeEffect of bi-directional excitation input on boiling water reactor scrammabilityYoshihiro GOTO0Yuichi KOIDE1Hirokuni ISHIGAKI2Yugo HYOTANI3Hitachi, Ltd., Research & Development Group, Center for Technology Innovation – Mechanical EngineeringHitachi, Ltd., Research & Development Group, Center for Technology Innovation – Mechanical EngineeringHitachi-GE Nuclear Energy, Ltd.Hitachi-GE Nuclear Energy, Ltd.When a large earthquake occurs, a boiling water reactor is automatically shutdown through the insertion of control rods among fuel assemblies. A fuel assembly can vibrate in-plane when two seismic waves act on it in directions at right angles to each other in a horizontal plane. Although the state of contact between a control rod and fuel assembly is different from that with one directional input, the effect of the difference on scram time is not clear. In this study, we evaluated control rod insertability under bi-directional excitation inputs using a dynamic insertion model of control rod. Sine waves were used as input waves, and their frequency corresponds to the first natural frequency of a fuel assembly. By changing the amplitude and phase difference of the input wave, we simulated the behaviors of the fuel assembly, such as vibration direction and whirling under bi-directional excitation inputs. As a result, we concluded that a comparatively long scram time was obtained when the fuel assembly vibrated in the direction orthogonal to the surface of the control rod blade. Additionally, as the phase difference between two horizontal inputs increased, there was increase in the scram time because the number of contacts between the control rod and the fuel assembly increased.https://www.jstage.jst.go.jp/article/transjsme/86/889/86_20-00227/_pdf/-char/enbwrseismic scrammabilitycontrol rodseismic motionbi-directional horizontal loads |
| spellingShingle | Yoshihiro GOTO Yuichi KOIDE Hirokuni ISHIGAKI Yugo HYOTANI Effect of bi-directional excitation input on boiling water reactor scrammability Nihon Kikai Gakkai ronbunshu bwr seismic scrammability control rod seismic motion bi-directional horizontal loads |
| title | Effect of bi-directional excitation input on boiling water reactor scrammability |
| title_full | Effect of bi-directional excitation input on boiling water reactor scrammability |
| title_fullStr | Effect of bi-directional excitation input on boiling water reactor scrammability |
| title_full_unstemmed | Effect of bi-directional excitation input on boiling water reactor scrammability |
| title_short | Effect of bi-directional excitation input on boiling water reactor scrammability |
| title_sort | effect of bi directional excitation input on boiling water reactor scrammability |
| topic | bwr seismic scrammability control rod seismic motion bi-directional horizontal loads |
| url | https://www.jstage.jst.go.jp/article/transjsme/86/889/86_20-00227/_pdf/-char/en |
| work_keys_str_mv | AT yoshihirogoto effectofbidirectionalexcitationinputonboilingwaterreactorscrammability AT yuichikoide effectofbidirectionalexcitationinputonboilingwaterreactorscrammability AT hirokuniishigaki effectofbidirectionalexcitationinputonboilingwaterreactorscrammability AT yugohyotani effectofbidirectionalexcitationinputonboilingwaterreactorscrammability |