“CAD-centric” Integrated Multi-physics
Simulation Predictive Capability for Plasma
Chamber Nuclear Components
Aligned with ReNew Thrust 15
Unlike FSP, the integrated modeling is progressed in a smaller scale fashion
A. Ying (UCLA), R. Reed (graduate student), R. Munipalli (HyPerCom)
Acknowledgements to graduate(d) students M. Narula, R. Hunt, and H. Zhang
(UCLA)
Others working on separate parts of the subject
M. Abdou, M. Ulrickson (and team), M. Sawan (and team),
M. Youssef, B. Merrill
FNST meeting
August 2, 2010
UCLA
1
Integrated Simulation Predictive Capability (ISPC) as a part
of ReNeW Thrust 15: Creating integrated models for attractive
fusion power systems
Today’s Trend in Simulation:
– Treat complexity of entire
problem
• Extreme geometric complexity
• Multi-physics, Multi-scales
– Inter-disciplinary approach
• Modernize codes & Interpret
phenomena from interrelated
scientific disciplines
– High accuracy & thorough
understanding at each level
– Interactive visualization and post
processing (Intelligent Expert
System)
ReNeW Thrust 15 Integrated Model
Objectives:
• Develop predictive modeling capability for
nuclear components and associated
systems that are science-based, wellcoupled, and validated by experiments
and data collection.
• Extend models to cover synergistic
physical phenomena for prediction and
interpretation of integrated tests and for
optimization of systems.
• Develop methodologies to integrate with
plasma models to jointly supply first wall
and divertor temperature and stress levels,
electromagnetic responses, surface
erosion, etc.
2
An integrated model tool potentially contributes to more
efficient FNST R&D
• Provide high level of accuracy and substantially reduce risk and cost for the
development of complex plasma chamber in-vessel components
• Facilitate simulation of normal and off normal operational scenarios.
• Offer capabilities for system optimization
• Allow insight and intuition into the interplay between key multi-physics
phenomena (occurring at a level where instruments cannot be installed.)
• Better understand the state of the operation through limited diagnostics
• The time-dependent BLKT outlet temperature can
be used in RELAP5 system code for heating
control analysis.
• The flow pattern and associated heat transfer
inside a FW/BLKT is very complex, which RELAP5
cannot model.
FW/BLKT temperature response with time with
water inlet temperature at 10K/h ramp-up rate.
376.5
Baking at inlet T increase at 10K/h
376
Tinlet
Toutlet
T_Max
T_Min
Cu
Be
Shield-SS
FW-SS
375.5
BLKT-12
CATIA model
Shield
Module
375
374.5
374
373.5
373
FW (Be)
372.5
0
200
400
600
Time (s)
“ITER Baking in progress”
800
1000
3
1200
CAD-centric modeling tools are being used in the US ITER
FW/Blanket Shield Design (design by analysis)
(led by Mike Hechler-ORNL and Mike Ulrickson-SNL)
Mechanical load
under a disruption
Snapshots of velocity magnitudes at
different pipes (BLKT-12 SM)
Nuclear heating profile
CFD/thermo-fluid
X-Y plane (8 cm
above mid-plane)
4
FW/BLKT-12
Design by analysis incorporating CAD model becomes even more
important in regard to first wall panels shaped as local limiters
ITER FW/shield design still evolving
• The heat flux profile is extremely non-uniform:
heat flux as high as 5 MW/m2 (7.5 MW start-up
and ramp down), 40% of wall EHF modules
• A shaped FW design brings forth the
importance of using “prototype” in the analysis
location
Peak heat flux
Rows or panels
affected
Inboard : start-up
4.4 MW/mm²
3,4
Outboard
3.6 MW/m²
14,15,16,17
Shine thru
4.0 MW/m²
6 panels on rows
15,16
Top
4.6 MW/m²
7-8-9-10
In recent design,
slot was removed
Reference: R. Mitteau et. al., Heat loads and shape design of
the ITER first wall, ISFNT-9 (2009)
CuCrZr
CuCrZrVon Mises (Pa)
5
Simulation performed on an engineering CAD model allows
practical design assessments
High temperature at
upper structures
• Location of the instrument and the associated
perturbation to the data
• Analysis with a detailed geometric drawing
with instrumentations in-place needed
Velocity :m/s
Initial results
with
simplified
geometry
& operating
condition
PbLi
velocity
PbLi
velocity
Mid-plane nuclear heating (gamma: left; neutron: right)
W/cc
Thermomechanics Analysis
Inlet to 2nd FW
cooling panel


Proper manifold designs to
provide uniform flow
distributions among many
parallel flow paths
Adequate cooing to all parts
DCLL He-coolant
inlet manifold
Stress
concentration
He-velocity
ISPC can potentially reduce risk and cost of the component development
6
7
What numerical software are available for CAD-centric
integrated model?
(many neutronics codes available: deterministic or Monte Carlo)
MCNP(X)
MCNPX
Native
Geometry
ITER 40o A-lite
Neutronic model
MOAB & CGM
CAD
Voxels
(Other)
DAG-MCMP
ITER FW
Panel
Attila: Commercial Software
Tetrahedral mesh
Attila is now being used
MCNP – MCAM
to calculate radioactivity
Community Developed
of components
Orthogonal mesh
Hybrid code ADVANTG
ORNL
(MCNP + Denovo)
8
Total (neutron + photon) flux
Solving individual physics using its optimized numerical technique
and running simultaneously with a smart transfer of information
• Adopting one numerical technique for all simulations in ISPC can limit the size
of the problem and is undesirable.
Overcoming CAD discrepancy
(e.g. overlapping) is common
source of difficulty for MCNP
Sample analysis codes and mesh requirements in ISPC
Physics
Analysis code
Mesh specification
Neutronics
MCNP
Monte Carlo mesh tally (cell based)
Attila
Unstructured tetrahedral mesh
(node based)
OPERA
(Cubit)
Unstructured tetrahedral (Hex-)
mesh (node based)
ANSYS
Unstructured Hex/Tet mesh (node
based and edge based formulations)
CFD/
Thermofluids
SC/Tetra
Unstructured hybrid mesh (node
based)
Fluent/CFX
etc.
Unstructured hybrid mesh (cell
based)
MHD
HIMAG
Unstructured hybrid mesh (cell
based)
Electromagnetics
Structural
analysis
ANSYS/
ABAQUS
Unstructured second order Hex/Tet
mesh (node based)
Species
transport
COMSOL or
others: TMAP,
ASPEN
Unstructured second order mesh
(node based)
Safety
RELAP5-3D
MELOCR
System representation code
DAG-MCNP (UW)
Imprinting
A
F
B
D
Merging
E
C
9
A multi-disciplinary effort
• Integration of computational software forms the heart of FNST performance
prediction
• Data mapping and interpolation across various analysis meshes/codes has to
be fast, accurate and satisfy physical conservation laws
• Large scale simulation, leading-edge high performance computing, advanced
computational methods, and the development and application of new mathematical
models
Verification & Validation
Radioactivity
Transmutation
Neutronics
Radiation
damage rates
Thermofluid
MHD
Species
(e.g. T2)
transport
Structure/
thermomechanics
Electromagnetics
Coupled effect
Special
module
Safety
e.g. source
Material database/Constitutive equations/ Irradiation effect
Mesh services
Adaptive mesh/
mesh refinement
Data Management:
Interpolation
Neutral format
Time step control for
transient analysis
Visualization
Partitioning Parallelism
CAD- Geometry
10
ISPC Design Process Flow
FW/Plasma Facing
Surface Phenomena
• Maintain consistency in the geometric
representation among the analysis codes
• The CAD-based solid model is the common
q  profile
element across physical disciplines
FW/PFC Thermo-fluid
Neutron source profile
Neutronics
CAD Model
Electromagnetics
DMS
q”
*
DMS
FUN
Thermo-fluid
& LM MHD
3-D design iterative
DMS
*
Stress/DeformationAnalysis
assessment important
FUN
Specialized
physics models
Structural Support
Tremendous work for
ITER FW/SB at SNL
specialized user FUNction
Data Mapping Script
Species Transport
FUN
Safety or
Transient events
Need experimental data for code verification & validation
Within ITER project, some R&D being carried out and providing
data for design support and code benchmark
US-CHF-200638
Data (2 MW/m2)
Calcualtion (No constraint)
Data (3MW/m2)
Calculation (No constrain)
Data (4MW/m2)
Calcualtion (No constraint)
Data (4.6MW/m2)
Calculation (No constraint)
320
300
260
2mpers-RF
TC-01
TC-03
TC-05
SC/T-01
SC/T-03
SC/T-05
240
220
280
200
180
260
160
240
140
220
120
60
TC locations: 12 mm from the side and 1.5 mm from the top
70
80
90
100
110
120
Time (s)
200
0
2
4
6
distance into heating (cm)
8
10
TCs installed in the mockup have provided data
Jet impingement
10
10
RF-CHF
He inlet
150
US-CHF mock-up
Verification/validation needed on integration method
He outlet
Temperature and He flow 12
characteristics under 10 MW/m2
“How to” incorporate a bigger resource into ISPC?
Similar efforts are being pursued in various fields:
• within DOE Vision 21 project (Improved asset optimization
by integrating ASPEN PLUS and FLUENT)
• Nuclear Energy and Simulation Hub
• FSP (Fusion Simulation Project)
Advanced computational tools are continuously
being developed in various projects:
SciDAC, ITAPS, CCA, etc.
Nuclear Energy Innovation Hub
“to apply existing modeling and simulation
capabilities to create a user environment
that allows engineers to create a simulation
of a currently operating reactor that will act
as a "virtual model" of that reactor.---”
• Look for synergism
• Not re-inventing the wheel but riding on state-of-the-art methodology
13
Next Steps
How do you see this moving forward?
Three activities (ITER FW/shield design, TBM program, and FNSF assessment
study) provide mechanism, panorama, and opportunity for the development/
benchmark/test of the idea to the extent possible.
However, a substantial effort requires FSP-like or NESH-like commitment
Near term goal
• Continue to build/enhance interface and data management (increase
degree of automation)
• Establish test cases to further explore the limit of the capability
Example test cases
• Enhance existing neutronics computational platform for TBM radioactive dose
calculations extended to ITER port cell area
• FNSF tritium breeding assessment through a complete 3-D base breeding
blanket exploratory design analysis
• Develop schemes to link to plasma facing surface phenomena, and address FW
tritium inventory and permeation losses
• Periodic recovery of implanted tritium has an impact on the TBR requirement;
however, its degree of impact is affected by losses from tritium permeation into FW
coolant
14
Summary
• Adopt the state-of-the-art computer technique, high-powered computing,
advanced modeling and simulation that is 3-dimensional, high-resolution
• Develop highly integrated predictive capabilities for many cross-cutting
scientific & engineering disciplines and deliver faster and more detailed
insights into the R&D of in-vessel FNST components and systems
Imagine if critical performance parameters can
be projected and examined in advance----
Troidal coil
First wall
/Blanket
Plasma
Test Blanket
Module(TBM)
• The goal of an integrated simulation
effort then is to be able to model and
design a complete DEMO system
including irradiation effects,
thermofluid/MHD, temperatures and
mechanical loads, tritium accountability
in entire system (tritium retention, and
tritium production and transport
processes), and FW/divertor erosion.
Divertor
6.2m
15