Finite Element Analysis Model for Estimating the Dynamic Crush Strength of the Spacer Grid Assembly for PWRs


Article Preview

The spacer grid assembly, which is an interconnected array of slotted grid straps and welded at the intersections to form an egg crate structure, is one of the main structural components of the nuclear fuel assemblies of a Pressurized light Water Reactor (PWR). The spacer grid assembly is structurally required to have enough crush strength under lateral loads due to lateral seismic accelerations, lateral Loss Of Coolant Accident (LOCA) blowdown forces, and shipping and handling loads so that the fuel rods are maintained within a coolable geometry, and that the control rods are able to be inserted. The ability of the spacer grid assembly to resist the lateral loads is usually characterized in terms of its dynamic and static crush strengths, which are acquired from the relevant tests. In this study, dynamic buckling tests and finite element analyses on spacer grid assembly specimens are carried out. As a result of the comparisons, the analysis results are in good agreement with the test results to within an 8 % difference range. Therefore, we could predict the crush strength of a spacer grid assembly in advance before performing the dynamic buckling test.



Key Engineering Materials (Volumes 324-325)

Edited by:

M.H. Aliabadi, Qingfen Li, Li Li and F.-G. Buchholz




K. N. Song et al., "Finite Element Analysis Model for Estimating the Dynamic Crush Strength of the Spacer Grid Assembly for PWRs ", Key Engineering Materials, Vols. 324-325, pp. 1011-1014, 2006

Online since:

November 2006




[1] H.J. Kunz, R. Schiffer, and K-N Song: Fuel Assembly Mechanical Design Manual; Siemens/KWU Work-Report U6 312/87/e326 (1987).

[2] H.D. Hibbit, G.I. Karlsson and E.P. Sorensen: ABAQUS/Explicit Users' Manual Version 6. 5 (2005).

[3] ASTM E8M-99: Standard Test Methods for Tension Testing of Metallic Materials (1999).

[4] K-H Yoon, W-K In, H-S Kang, and K-N Song: ICONE 12-49106 (2003).

[5] Electronic Data Systems Corporation: I-DEAS Master Series Version 8m3; Structural Dynamics Research Corporation; OH USA (2000).

[6] K-H Yoon, S-P Heo, K-N Song, and Y-H Jung: Computers & Structures Vol. 82 (2004), p.2221.

[7] K-H Yoon and K-N Song: SMIRT 18-1538 (2001).