Outline Proposal: FETCH Modelling of the MIPR

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Outline Proposal FETCH Modelling of the MIPR

• Matthew Eaton, Christopher Pain,
• Jeff Gomes, Brendan Tollit, Tony Goddard,
• Gerard Gorman and Matthew Piggott
• Applied Modelling and Computation Group

Babcock Wilcox 05/12/2008
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Team Members

• Dr Matt Eaton (RT and Uncertainty Analysis)
  Principal Investigator
• Prof Chris Pain (Numerical Analysis and
  Multiphysics) Head of the AMCG and Co-I
• Prof Tony Goddard (RT and Reactor Physics)
  Senior Adviser and Co-I
• Dr Matt Piggott (CFD and Turbulence) Co-I
• Dr Gerard Gorman (Parallel Mesh Adaptivity and
  QA) Co-I
• Dr Jeff Gomes (Multiphysics and CMFD) Funded
  PDRA
• Mr Brendan Tollit (Multiphysics and Reactor
  Physics) Funded PDRA

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Coupled CMFD and RT Models FETCH
WIMS9
Tabulated Group Constants
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MIPR
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Goals

• Investigation of transient fault modelling of the
  MIPRs under numerous prescribed conditions

• Investigating MIPRs stability at high power
  densities

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Challenges

• 3D Complex Geometry heterogeneous modelling

• Phase change Boiling and Condensation

• Parameterisation of the radiolytic gas bubbles
  nucleation on the cooling coil and submerged
  surfaces

• Large Scale Fully-Coupled RT/CMFD-TH

• Automated and Continuous QA

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Work-Packages

• WP1 Neutronics modelling of MIPR and 50KW
  Operational reactor

• WP2 Development of 2-D RZ and 3-D non-explicit
  geometry coupled RT/CMFD-TH MIPR model

• WP3 Initial 50KW test cases and Accident
  scenarios for 2-D RZ and 3-D non-explicit
  geometry

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Work-Packages

• WP4 Large Scale Modelling using FETCH and
  parallel visualization interfacing with PARAVIEW

• WP5 Development of a 3-D explicit geometry
  coupled RT/CMFD-TH MIPR model and a 50KW fully
  operational test-case

• WP6 Initial 50KW test-cases and Accident
  scenarios for 3-D explicit geometry model of the
  MIPR

• WP7 Automated QA, RT/CMFD-TH Interfaces,
  Documentation and Deliverables

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WP1 Neutronics Modelling of MIPR and 50KW
Operational Reactor

• Task 1 Development of 2-D axi-symmetric RZ model
  and 3-D non explicit geometry (parameterization
  of control rods and cooling coils) with nuclear
  cross-section data generated using WIMS

• Task 2 Development of a 3-D explicit geometry
  model of the MIPR using GID and RHINO and
  explicit sub-group spatial/energy self-shielding
  phenomena in FETCH

• Task 3 Interfacing FETCH with the SCALE US NRC
  criticality code for generation of nuclear data
  for the MIPR

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WP2 Development of 2-D RZ and 3-D non-explicit
geometry coupled RT/CMFD-TH MIPR model

• Task 1 Parameterization of the heat transfer
  aspects of the cooling coils

• Task 2 Parameterization of the radiolytic gas
  bubble nucleation on cooling coil and control rod
  surfaces and within the solution volume of the
  MIPR

• Task 3 Parameterization of homogeneous and
  heterogeneous (submerged surfaces) boiling

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WP3 Possible 50KW test cases and Accident
scenarios for 2-D RZ and 3-D non-explicit
geometry

• 1 Inadvertent withdrawal of control rods

• 2 Introduction of excess fuel into solution

• 3 Changing the fuel U/H ratio by introducing
  hydrogenous (excess acid, coolant tube leak etc)
  material into the solution core

• 4 Increased fuel solution density due to rise of
  dome pressure or drop of fuel temperature

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WP3 Possible 50KW test cases and Accident
scenarios for 2-D RZ and 3-D non-explicit
geometry (cont)

• 5 Fuel solution leakage

• 6 Hydrogen deflagration and/or detonation

• 7 Overpower without scramming of control rods

• 8 Loss of pumping power

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WP4 Parallel FETCH interface and parallel
visualization interfacing with PARAVIEW

• Task 1 Interface module of CMFD/RT
  parallelisation

• Task 2 Distributed and multi-core processor
  testing on ICT facilities.

• Task 3 Parallel visualization

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WP5 Development of a 3-D explicit geometry
coupled RT/CMFD-TH MIPR model and a 50KW fully
operational test-case

• Task 1 Parameterization of the nucleation on
  cooling coil and control rod surfaces and within
  the solution volume of the MIPR

• Task 2 Parameterization of homogeneous and
  heterogeneous (submerged surfaces) boiling

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WP6 Possible 50KW test-cases and Accident
scenarios for 3-D explicit geometry model of the
MIPR (repeated from previous)

• 1 Inadvertent withdrawal of control rods

• 2 Introduction of excess fuel into solution

• 3 Changing the fuel U/H ratio by introducing
  hydrogenous (excess acid, coolant tube leak etc)
  material into the solution core

• 4 Increased fuel solution density due to rise of
  dome pressure or drop of fuel temperature

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WP6 Possible 50KW test-cases and Accident
scenarios for 3-D explicit geometry model of the
MIPR (cont)

• 5 Fuel solution leakage

• 6 Hydrogen deflagration and/or detonation

• 7 Overpower without scramming of control rods

• 8 Loss of pumping power

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WP7 Automated QA and RT/CMFD-TH Interfaces and
Documentation

• Task 1 Verification and Validation Suite
  Procedures Bubbly solutions initial benchmarks
  (TRACY, SILENE, Aparatus B, CRAC, etc)

• Task 2 Users-orientated interface for the RT and
  CMFD-TH Modules Spud-Diamond and CAD-based
  Mesh-generator

• Task 3 Automated and Continuous QA SVN,
  Buildbot

• Task 4 Complete Wiki-based documentation

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Explicit Heterogeneous Modelling
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Similar PBR Mesh to homogeneous 3-D model

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Explicit Heterogeneous Modelling

• Spatial variation in flux and power around
  cooling coils (water moderator) and
  control/safety rods effecting spatial shielding
  of multi-group cross-section data subgroup
  treatment in full 3-D. Also movement of control
  rods only approximately taken into account e.g.
  in rod ejection accidents.
• Spatial variation in radiolytic gas and steam. In
  reality this may provide significant effects on
  heat transfer between coils and the Uranyl
  Nitrate solution as well as cross-sections.

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Explicit Heterogeneous Modelling

• Flow paths in homogeneous 2-D RZ and 3-D
  homogeneous models only approximately modelling
  the full heterogeneous flow paths. e.g. effects
  of cooling coils may provide significant
  distortions in flow paths within the reactor with
  consequent perturbations on the power.
• Validation and verification provides a more
  rigorous
• justification for the modelling to the US NRC if
  an explicit model has been performed.

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Deliverables and Post-Work
i) homogeneous (2D 3D) and explicit FETCH
models ii) continuous regression testing iii)
user friendly interface for possible BW use iv)
analysis of MIPR transients

• FETCH use at BW and post project