Physics aspects in the design of heterogeneous cores. [LMFBR]

Conference · Sun Jan 01 04:00:00 EST 1978

OSTI ID:8307222

Barthold, W. P.; Beitel, J. C.

In unprotected loss-of-flow transients in large LMFBRs the reactor may become super-prompt critical on sodium voiding alone. To preclude an energetic disassembly the subsequent fuel motion must be monotonically dispersive. It is difficult if not impossible to resolve details of fuel motion under super-prompt critical conditions at very high power levels. However, if the sodium void reactivity is reduced to zero or near zero values, the sensitivity of the energetics to details of fuel motion can be greatly reduced and even under pessimistic accident scenarios less energetic termination of the transient is expected. Therefore, there is a strong incentive for designing reactors that have a near zero value of sodium void reactivity. Among such designs, the heterogeneous configurations that consist of successive radial core and blanket zones are most promising. The enhancement of neutron leakage from the core zones into the internal blanket zones results in a low sodium void reactivity because of the increase in the leakage component and decrease in the spectral component of the void reactivity.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 8307222
• Report Number(s): CONF-780401--13
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210500* -- Power Reactors
Breeding
ALKALI METALS
BREEDER REACTORS
DESIGN
ELEMENTS
EPITHERMAL REACTORS
FAST REACTORS
FBR TYPE REACTORS
HETEROGENEOUS EFFECTS
KINETICS
LIQUID METAL COOLED REACTORS
LMFBR TYPE REACTORS
METALS
REACTIVITY
REACTIVITY COEFFICIENTS
REACTIVITY INSERTIONS
REACTOR COMPONENTS
REACTOR CORES
REACTOR KINETICS
REACTORS
SODIUM
VOID COEFFICIENT