Neutron streaming in pebble beds
The fuel spheres in the core of a pebble-bed reactor are mainly distributed statistically. Regular configurations appear only near the walls and on the bottom of the core. A statistical distribution has been studied by means of a proper mock up. For this purpose the coordinates of 3024 sphere centers were defined by measurements so that Monte Carlo games for neutron diffusion could be established. From these results as well as from Monte Carlo calculations for the cubic and tetrahedral sphere configurations, the diffusion constants and the first two mean moments h/sup -/ and h/sup 2 -/ of the passage lengths in the holes were determined. Under the assumption that no correlation exists between the passage lengths in the holes and in the balls, an exact formula for the diffusion lengths was derived using h/sup 2 -//(h)/sup 2 -/.
- Research Organization:
- INTERATOM, Internationale Atomreaktorbau GmbH Abteilung Neutronenphysik, Postfach D-5060 Bergisch Gladbach
- OSTI ID:
- 6986961
- Journal Information:
- Nucl. Sci. Eng.; (United States), Journal Name: Nucl. Sci. Eng.; (United States) Vol. 76:3; ISSN NSENA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
210300* -- Power Reactors
Nonbreeding
Graphite Moderated
ANALOG SYSTEMS
BARYONS
CONFIGURATION
COORDINATES
DIFFERENTIAL EQUATIONS
DIFFUSION
DIFFUSION LENGTH
DIMENSIONS
DISTRIBUTION
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
FUEL ELEMENTS
FUEL SPHERES
FUNCTIONAL MODELS
GAS COOLED REACTORS
HADRONS
HOMOGENEOUS REACTORS
LENGTH
MATHEMATICAL MODELS
MOMENTS METHOD
MONTE CARLO METHOD
NEUTRAL-PARTICLE TRANSPORT
NEUTRON DIFFUSION EQUATION
NEUTRON TRANSPORT
NEUTRONS
NUCLEONS
PEBBLE BED REACTORS
RADIATION STREAMING
RADIATION TRANSPORT
REACTOR COMPONENTS
REACTOR CORES
REACTOR SIMULATORS
REACTORS
SIMULATORS
SOLID HOMOGENEOUS REACTORS
STATISTICAL MODELS