ML20128D807
| ML20128D807 | |
| Person / Time | |
|---|---|
| Site: | Oregon State University |
| Issue date: | 02/01/1993 |
| From: | Oregon State University, CORVALLIS, OR |
| To: | |
| Shared Package | |
| ML20128D794 | List: |
| References | |
| NUDOCS 9302100233 | |
| Download: ML20128D807 (1) | |
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w increase in loading would result in an increase in power density of about 2%. Similarly, a minimum erbium content of 1.1% in an element is about 30% less than the design value. This variation would result in an increase in power density of only about 6%. An in-crease in local power density of 6% reduces the safety margin by, at most, 10%. The maximum hydrogen-to-zirconium ratio of 1.65 could result in a maximum stress under accident conditions in the fuel element clad about a factor of two greater than the value resulting from a hydrogen-to-zirconium ratio of 1.60. However, this increase in the clad stress during an accident would not exceed the rupture strength of the clad. When standard and FLIP fuel elements are used in mixed cores, visual identification of types of elements is necessary to verify correct fuel loadings,
- b. A maximum uranium content of 9 wt-% in a standard TRIGA element is about 6% greater than the design value of 8.5 wt-%. Such an in-crease in loading would result in an _ increase in power density of less than 6%. An increase in local power density of 6% reduces the safety margin by, at most, 10%. The maximum hydrogen-to-zirconium ratio of 1.8 could result in a maximum stress under accident condi-tions in the fuel element clad about a factor of two greater than-the value resulting from a hydrogen-to-zirconium ratio of 1.60.
However, this increase in the clad stress during an accident would not exceed the rupture strength of the clad. When standard and FLIP fuel elements are used in mixed cores, visual identification of types of elements is necessary to verify correct fuel loadings.
5.2 REACTOR CORE Aeolicabilily. This specification applies to the configuration of fuel and in-core experiments.
Ob.iective. The objective is to assure that provisions are made to restrict the arrangement of fuel elements and experiments so as to provide assurance that excessive power densities will not be produced.
Specifications,
- a. The core shall be an arrangement of TRIGA uranium-zirconium hydride fuel-moderator elements positioned in the reactor grid plate.
- b. The TRIGA core assembly may consist of standard fuel . elements, FLIP fuel elements, or a combination thereof (mixed core). Any opera-tional mixed core assembly shall have no less than 80 FLIP fuel ele-ments, located in a contiguous, central region.
- c. The fuel shall be arranged in a close-packed configuration except for single element positions occupied by in-core experiments, experimental facilities, graphite dumaies, aluminum dummies, stain-less steel dummies, control rods, and startup sources.
PD0 o$ obobO$43 Amendment No. 13 P PDR
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