0
Research Papers: Design and Analysis

Comparative Study on Reactor Pressure Vessel Failure Behaviors With Various Geometric Discontinuities Under Severe Accident

[+] Author and Article Information
Jianwei Zhu

Institute of Process Equipment
and Control Engineering,
Zhejiang University of Technology,
Chaowang Road 18#,
Hangzhou, Zhejiang 310032, China;
School of Mechatronics and
Automobile Engineering,
Huzhou Vocational and Technical College,
Xuefu Road 299#,
Huzhou, Zhejiang 313000, China
e-mail: stormflash1978@163.com

Jianfeng Mao

Engineering Research Center of Process
Equipment and Re-Manufacturing,
Ministry of Education,
Institute of Process Equipment
and Control Engineering,
Zhejiang University of Technology,
Chaowang Road 18#,
Hangzhou, Zhejiang 310032, China
e-mail: maojianfeng@zjut.edu.cn

Shiyi Bao

Institute of Process Equipment
and Control Engineering,
Zhejiang University of Technology,
Chaowang Road 18#,
Hangzhou, Zhejiang 310032, China
e-mail: bsy@zjut.edu.cn

Lijia Luo

Institute of Process Equipment
and Control Engineering,
Zhejiang University of Technology,
Chaowang Road 18#,
Hangzhou, Zhejiang 310032, China
e-mail: lijialuo@zjut.edu.cn

Zengliang Gao

Engineering Research Center of Process
Equipment and Re-Manufacturing,
Ministry of Education,
Institute of Process Equipment
and Control Engineering,
Zhejiang University of Technology,
Chaowang Road 18#,
Hangzhou, Zhejiang 310032, China
e-mail: zlgao@zjut.edu.cn

1Corresponding authors.

Contributed by the Pressure Vessel and Piping Division of ASME for publication in the JOURNAL OF PRESSURE VESSEL TECHNOLOGY. Manuscript received March 20, 2016; final manuscript received January 6, 2017; published online February 3, 2017. Assoc. Editor: Hardayal S. Mehta.

J. Pressure Vessel Technol 139(2), 021214 (Feb 03, 2017) (10 pages) Paper No: PVT-16-1051; doi: 10.1115/1.4035697 History: Received March 20, 2016; Revised January 06, 2017

The so-called “in-vessel retention (IVR)” is a basic strategy for severe accident (SA) mitigation of some advanced nuclear power plants (NPPs). The IVR strategy is to keep the reactor pressure vessel (RPV) intact under SA like core meltdown condition. During the IVR, the core melt (∼1327 °C) is collected in the lower head (LH) of the RPV, while the external surface of RPV is submerged in the water. Through external cooling of the RPV, the structural integrity is assumed to be maintained within a prescribed period of time. The maximum thermal loading is referred to critical heat flux (CHF) on the inside, while the external surface is considered to perform in the environment of the boiling crisis point (∼130 °C). Due to the high temperature gradients, the failure mechanisms of the RPV is found to span a wide range of structural behaviors across the wall thickness, such as melt-through, creep damage, plastic yielding as well as thermal expansion. Besides CHF, the pressurized core meltdown was another evident threat to the RPV integrity, as indicated in the Fukushima accident on 2011. In illustrating the effects of internal pressures and individual CHF on the failure behaviors, three typical RPVs with geometric discontinuity caused by local material melting were adopted for the comparative study. Through finite-element method (FEM), the RPV structural behaviors were investigated in terms of deformation, stress, plastic strain, creep, and damage. Finally, some important conclusions are summarized in the concluding remark. Such comparative study provides insight and better understanding for the RPV safety margin under the IVR condition.

Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

The scheme of a RPV in the core meltdown scenario and its cut vessel segments

Grahic Jump Location
Fig. 2

FE-models of three typical RPVs with geometric discontinuity in lower head: (a) equal, (b) gradual, and (c) notched

Grahic Jump Location
Fig. 3

Inner temperature and wall thickness profiles used in the simulation under CHFs

Grahic Jump Location
Fig. 4

Temperature contours among various geometric discontinuities

Grahic Jump Location
Fig. 5

The total displacement distribution among the highly eroded regions at failure time

Grahic Jump Location
Fig. 6

The total displacement distribution among the axial direction

Grahic Jump Location
Fig. 7

Maps of equivalent (von Mises) stress distribution before creep occurrence

Grahic Jump Location
Fig. 8

Maps of equivalent plastic strain distribution before creep occurrence

Grahic Jump Location
Fig. 10

Total displacement distribution along the axial direction after 100 h

Grahic Jump Location
Fig. 9

Total displacement distribution among various highly eroded regions after 100 h

Grahic Jump Location
Fig. 11

Maps of equivalent (von Mises) stress distribution after 100 h creep time

Grahic Jump Location
Fig. 12

Maps of equivalent plastic strain distribution after creep occurrence

Grahic Jump Location
Fig. 13

Comparison of equivalent stress distributions across Path 1 for various geometric discontinuities

Grahic Jump Location
Fig. 14

Comparison of equivalent stress distributions across Path 2 for various geometric discontinuities

Grahic Jump Location
Fig. 15

The comparison of creep and plastic damage distributions across the Path 1 after 100 creep hours

Grahic Jump Location
Fig. 16

The comparison of creep and plastic damage distributions across the Path 2 after 100 creep hours

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In