Space--time dynamics of a fast breeder reactor for localized disturbances

Journal Article · Sun Jan 01 04:00:00 EST 1978 · Nucl. Sci. Eng.; (United States)

OSTI ID:5024976

Doshi, J B; Grossman, L M

A method of analysis is developed for nuclear reactor accident initiating events that are localized in space. The method is based on a flux factorization technique, accounting for the flux shape changes taking place near the region of perturbation. In the steady state, the neutron shape functions are expanded in a series of eigenfunctions of the steady-state group removal operator. During the unsteady state, the time-dependent group shape functions are expanded in a series of the same stationary eigenfunctions with time-dependent Fourier coefficients. An auxiliary function is added to this expansion to take account of the spatial variation of the spectral hardening of neutrons in the immediate vicinity of the disturbed region. From the resulting representation of the group shape functions, the equations to be satisfied by the time-dependent Fourier coefficients and the time-dependent auxiliary shape function due to the disturbed region are developed consistently. A typical large (1000-MW(e)) liquid-metal fast breeder reactor with two radial core zones of different enrichments is analyzed by the above method. The transient initiating perturbation is taken to be a specified rate of coolant voiding from a single subassembly in the reactor core. The results show a strong dependence of the reactivity added on the radial location of the voiding perturbation and on the rate of voiding.

• Research Organization: Univ. of California, Berkeley
• OSTI ID: 5024976
• Journal Information: Nucl. Sci. Eng.; (United States), Journal Name: Nucl. Sci. Eng.; (United States) Vol. 65:1; ISSN NSENA
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210500 -- Power Reactors
Breeding
22 GENERAL STUDIES OF NUCLEAR REACTORS
220900* -- Nuclear Reactor Technology-- Reactor Safety
ACCIDENTS
BREEDER REACTORS
DISTRIBUTION
EPITHERMAL REACTORS
FAST REACTORS
FBR TYPE REACTORS
KINETICS
LIQUID METAL COOLED REACTORS
LMFBR TYPE REACTORS
LOSS OF FLOW
MATHEMATICAL MODELS
REACTIVITY
REACTIVITY INSERTIONS
REACTOR ACCIDENTS
REACTOR KINETICS
REACTORS
SPATIAL DISTRIBUTION
TIME DEPENDENCE
VOID FRACTION