skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Challenges in structural analysis for deformed nuclear reactivity assessments.

Conference ·
OSTI ID:1026926

Launch safety calculations for past space reactor concepts have usually been limited to immersion of the reactor in water and/or sand, using nominal system geometries or in some cases simplified compaction scenarios. Deformation of the reactor core by impact during the accident sequence typically has not been considered because of the complexity of the calculation. Recent advances in codes and computing power have made such calculations feasible. The accuracy of such calculations depends primarily on the underlying structural analysis. Even though explicit structural dynamics is a mature field, nuclear reactors present significant challenges to obtain accurate deformation predictions. The presence of a working fluid is one of the primary contributors to challenges in these predictions. The fluid-structure interaction cannot be neglected because the fluid surrounds the nuclear fuel which is the most important region in the analysis. A detailed model of a small eighty-five pin reactor was built with the working fluid modeled as smoothed particle hydrodynamic (SPH) elements. Filling the complex volume covered by the working fluid with SPH elements required development of an algorithm which eliminates overlaps between hexahedral and SPH elements. The results with and without the working fluid were found to be considerably different with respect to reactivity predictions.

Research Organization:
Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC04-94AL85000
OSTI ID:
1026926
Report Number(s):
SAND2010-6585C; TRN: US1105148
Resource Relation:
Conference: Proposed for presentation at the Nuclear Emerging Technologies Symposium (NETS) 2010 held February 7-10, 2011 in Albuquerque, NM.
Country of Publication:
United States
Language:
English