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

Title: STRUCTURAL ANALYSIS OF ZIRCALOY FUEL-ELEMENT CONTAINERS FOR THE NS SAVANNAH REACTOR

Abstract

Structural evaluations were made of the 15% cold-worked Zircaloy fuel- element containers proposed for the NS Savannah reactor. These evaluations, which are consistent with the Navy Code, permitted the sizing of components so that under conservative loading conditions both stress and deflection limitations would be met. The necessary design modifications were specified for the fuel- element container assembly. (auth)

Authors:
Publication Date:
Research Org.:
Oak Ridge National Lab., Tenn.
OSTI Identifier:
4666748
Report Number(s):
ORNL-TM-483
NSA Number:
NSA-17-034411
DOE Contract Number:
W-7405-ENG-26
Resource Type:
Technical Report
Resource Relation:
Other Information: Orig. Receipt Date: 31-DEC-63
Country of Publication:
United States
Language:
English
Subject:
METALS, CERAMICS, AND OTHER MATERIALS; EXPONENTIAL PILES; FUEL CANS; FUEL ELEMENTS; MECHANICAL STRUCTURES; NSR; PLANNING; REACTOR FUELING; STRESSES; VARIATIONS; ZIRCALOY

Citation Formats

Shobe, L.R. STRUCTURAL ANALYSIS OF ZIRCALOY FUEL-ELEMENT CONTAINERS FOR THE NS SAVANNAH REACTOR. United States: N. p., 1963. Web. doi:10.2172/4666748.
Copy to clipboard
Shobe, L.R. STRUCTURAL ANALYSIS OF ZIRCALOY FUEL-ELEMENT CONTAINERS FOR THE NS SAVANNAH REACTOR. United States. doi:10.2172/4666748.
Copy to clipboard
Shobe, L.R. Mon . "STRUCTURAL ANALYSIS OF ZIRCALOY FUEL-ELEMENT CONTAINERS FOR THE NS SAVANNAH REACTOR". United States. doi:10.2172/4666748. https://www.osti.gov/servlets/purl/4666748.
Copy to clipboard
@article{osti_4666748,
title = {STRUCTURAL ANALYSIS OF ZIRCALOY FUEL-ELEMENT CONTAINERS FOR THE NS SAVANNAH REACTOR},
author = {Shobe, L.R.},
abstractNote = {Structural evaluations were made of the 15% cold-worked Zircaloy fuel- element containers proposed for the NS Savannah reactor. These evaluations, which are consistent with the Navy Code, permitted the sizing of components so that under conservative loading conditions both stress and deflection limitations would be met. The necessary design modifications were specified for the fuel- element container assembly. (auth)},
doi = {10.2172/4666748},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Aug 19 00:00:00 EDT 1963},
month = {Mon Aug 19 00:00:00 EDT 1963}
}
Copy to clipboard
Technical Report:
View Technical Report
DOI:  10.2172/4666748
Save / Share:
Export Metadata
Save to My Library
You must Sign In or Create an Account in order to save documents to your library.

  • ; ;
    Nuclear comparisons were made of Zircaloy and stainless steel as fuel- element container materials in the N. S. SAVANNAH core I design. In order to make the comparison, a four-group model employing a combination of onedimensional S/sub n/ transport-theory and two-dimensional diffusion-theory calculations was devised. The main features of the analytical model are geometrical detail and the use of the S/sub n/ method to obtain transport-theory equivalent-boundary conditions at the surface of control rods. Application of the four-group model to the N. S. SAVANNAH core I design revealed that, relative to stainless steel fuel-element containers, a Zircaloy fuel-element container structuremore » would increase control rod worth by DELTA k = 0.043 and would increase core reactivity by DELTA k = 0.062 for the same fuel enrichment. Although these two fuelelement container materials produced slightly different power distributions, the over-all peak-to-average power ratio appeared to be the same. In order to complete the comparison, simple one-dimensional radial burnup cal culations were performed. The burnup calculations indicated that the heterogeneous effect of the fuel- element containers on control rod worth would allow a 60% increase in the reactivity lifetime of core I-type fuel elements in Zircaloy fuel-element containers relative to the reactivity lifetime attainable in stainless steel fuel- element containers. (auth)« less

  • ; ; ; ...
    The possibility of reducing fuel-cycle costs for the N.S. SAVANNAH by replacing the stainless steel fuelelement containers in the permanent reactor core structure by similar containers of a zirconium alloy was investigated. These containers, although not integral parts of the fuel-bearing components, are located within the active core and divide the core into 32 separate channels into which the fuel elements are placed. Areas of investigation included reactor physics, fuel-cycle economics, materials compatibility, structural design, and reactor hazards. A summary of the method of analysis and results is given for each area ot investigation. Calculations indicated that the substitution ofmore » Zircaloy containers would increase core reactivity about 6% DELTA k and control- rod worth about 4% DELTA k. Fuel-cycle costs would be reduced about 26%. Zircaloy-4 appears to be compatible with the reactor system, except for some uncertainty with respect to fretting corrosion, which can be resolved only by tests. The substitution of cold-worked Zircaloy for stainless steel in the container assembly would necessitate only minor design modifications. Although this evaluation is strictly applicable only to the N.S. SAVANNAH reactor, the results demonstrate the feasibility and advantages of using zirconium alloys for in-core capital-cost components. (auth)« less

  • ; ; ; ...
    An analysis is presented of the possible accidental release of activity following operation of the NS Savannah at Camden, N. J. In a maximum credible accident the resulting exposure does not exceed the proposed emergeney critcria, and it is concluded that exposures ensuing from potential accidents following operation of this ship reactor should not cause any undue hazard. (J.R.D.)

  • ;
    Two dimensional thermoelastic and inelastic stresses and deformation of typical LWR (PWR) and LMFBR (CRBR) claddings are evaluated by utilizing the following codes, for (1) Thermoelastic analysis (a) STRESS Code (b) SEGPIPE Code (2) Thermoinelastic analysis (a) Modified version of the GOGO code (b) One dimensional GRO-II code. The primary objective of this study is to analyze the effect of various local perturbations in the clad temperature field, namely eccentrically mounted fuel pellet, clad ovality, power tilt across the fuel and clad-coolant heat transfer variation on the cladding stress and deformation. In view of the fact that the thermoelastic analysismore » is always the first logical choice entering the structural field, it was decided to start the analysis with the two dimensional codes such as STRESS and SEGPIPE. Later, in order to assess the validity and compare the thermoelastic results to those obtained for actual reactor conditions, a two dimensional code, namely a modified version of the GOGO code, was used to account for inelastic effects such as irradiation and thermal creep and swelling in the evaluation. The comparison of thermoelastic and inelastic results shows that the former can be used effectively to analyze LWR fuel pin over 350 hours of lifetime under the most adverse condition and 500 hours of lifetime for an LMFBR fuel pin. Beyond that the inelastic solution must be used. The impact of the individual thermal perturbation and combinations thereof upon the structural quantity is also shown. Finally, the effect of rod displacement on the two dimensional thermal and structural quantities of the LMFBR fuel pin cladding is analyzed.« less

  • Primary, secondary, and thermal stresses were calculated and evaluated for the SNAP-8 developmental reactor fuel element cladding. The effects of fabrication and assembly stresses, as well as test and operational stresses were included in the analysis. With the assumption that fuel-swelling-induced stresses are nil, the analytical results indicate that the cladding assembly is structurally adequate for the proposed operation.