Preliminary study on applying the method of characteristics to pebble-bed HTR - 18637

Conference · Tue Nov 15 00:00:00 EST 2016

OSTI ID:23032718

Jian, Guo; Jiong, Guo; Fu, Li ^[1]

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1. Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education, Beijing, 100084, China (China)

Neutron transport in high temperature pebble-bed gas-cooled reactor, which is a promising generation IV reactor candidate with cylindrical core, graphite moderator and spherical TRISO coated particles fuel, is of great interest. However, the stochastic method namely Monte Carlo faces with tremendous simulation of particles and the conventional two-step method featured by homogenization only can give the scalar flux. In this paper, method of characteristics is trying to be applied to pebble bed reactor because of its advantages in arbitrary geometry and the ability to obtain solution in neutronically large domains. Some challenges occur when it comes to HTR. First, the amount of calculation and the memory requirement are huge due to the large quantities of spherical fuel and stochastic distribution of pebbles. Second, the arrangement of characteristics and ray tracing process is more complex comparing to LWR with cuboid geometry because the stochastic distribution of the spherical assemblies and the longer neutron mean free path in pebble bed HTR. Third, the treatment of the multiscale sphere fuel need be detail studied to determine the subdivision of flat source region. At present, preliminary research on this subject is undergoing. This paper is concentrated on the modeling of the pebble-bed reactor core by constructive solid geometry (CSG) which allows complex spatial models to be built using boolean operations, characteristics arrangement and the treatment of boundary condition. (authors)

• Research Organization: American Nuclear Society - ANS, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
• OSTI ID: 23032718
• Resource Relation: Conference: HTR 2016: International Topical Meeting on High Temperature Reactor Technology, Las Vegas, NV (United States), 6-10 Nov 2016; Other Information: Country of input: France; 9 refs.; available from American Nuclear Society - ANS, 555 North Kensington Avenue, La Grange Park, IL 60526 (US)
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
BOUNDARY CONDITIONS
COMPUTERIZED SIMULATION
CYLINDRICAL CONFIGURATION
FUEL ELEMENTS
FUEL PARTICLES
GEOMETRY
GRAPHITE
MEAN FREE PATH
MONTE CARLO METHOD
NEUTRON TRANSPORT
NEUTRONS
NUCLEAR FUELS
PEBBLE BED REACTORS
POROUS MATERIALS
REACTOR CORES
SCALARS
SOLIDS
SPHERICAL CONFIGURATION
STOCHASTIC PROCESSES