“CAD-centric” Integrated Multi-physics Simulation Predictive Capability for Plasma

Chamber Nuclear Components

1

Others working on separate parts of the subject

M. Abdou, M. Ulrickson (and team), M. Sawan (and team), M. Youssef, B. Merrill

A. Ying (UCLA), R. Reed (graduate student), R. Munipalli (HyPerCom)

Unlike FSP, the integrated modeling is progressed in a smaller scale fashion

FNST meetingAugust 2, 2010

UCLA

Aligned with ReNew Thrust 15

Acknowledgements to graduate(d) students M. Narula, R. Hunt, and H. Zhang (UCLA)

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Integrated Simulation Predictive Capability (ISPC) as a part of ReNeW Thrust 15: Creating integrated models for attractive

fusion power systems

ReNeW Thrust 15 Integrated Model Objectives:

•Develop predictive modeling capability for nuclear components and associated systems that are science-based, well-coupled, 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.

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)

“ITER Baking in progress”

An integrated model tool potentially contributes to more efficient FNST R&D

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372.5

373

373.5

374

374.5

375

375.5

376

376.5

0 200 400 600 800 1000 1200

Baking at inlet T increase at 10K/h

TinletToutletT_MaxT_MinCuBeShield-SSFW-SS

Time (s)

FW/BLKT temperature response with time with water inlet temperature at 10K/h ramp-up rate.

• 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.

• 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

BLKT-12 CATIA model

FW (Be)

Shield Module

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)

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Snapshots of velocity magnitudes at different pipes (BLKT-12 SM)

Nuclear heating profile

X-Y plane (8 cm above mid-plane) FW/BLKT-12

CFD/thermo-fluid

Mechanical load under a disruption

Design by analysis incorporating CAD model becomes even more important in regard to first wall panels shaped as local limiters

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• 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 fluxRows 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/m²6 panels on rows

15,16

Top 4.6 MW/m² 7-8-9-10

CuCrZrVon Mises (Pa)

In recent design, slot was removed

CuCrZr

Reference: R. Mitteau et. al., Heat loads and shape design of the ITER first wall, ISFNT-9 (2009)

ITER FW/shield design still evolving

Simulation performed on an engineering CAD model allows practical design assessments

6ISPC can potentially reduce risk and cost of the component development

Mid-plane nuclear heating (gamma: left; neutron: right)

W/cc

• Location of the instrument and the associated perturbation to the data

• Analysis with a detailed geometric drawing with instrumentations in-place needed

Thermomechanics Analysis

Proper manifold designs to provide uniform flow distributions among many parallel flow paths

Adequate cooing to all parts

DCLL He-coolant inlet manifold

He-velocity

High temperature at upper structures

PbLi velocity

PbLi velocity

Velocity :m/s

Stress concentration

Initial results with simplified geometry& operating condition

Inlet to 2nd FW cooling panel

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What numerical software are available for CAD-centric integrated model?

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Attila: Commercial SoftwareTetrahedral mesh

MCNP – MCAMCommunity Developed

Orthogonal mesh

DAG-MCMP

MOAB & CGMCAD Voxels

MCNP(X)MCNPXNative

Geometry (Other)

(many neutronics codes available: deterministic or Monte Carlo)

Hybrid code ADVANTG (MCNP + Denovo)

ITER FW Panel

Attila is now being used to calculate radioactivity of components

ITER 40o A-lite Neutronic model

Total (neutron + photon) flux

ORNL

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Solving individual physics using its optimized numerical technique and running simultaneously with a smart transfer of information

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)

Electro-magnetics

OPERA(Cubit)

Unstructured tetrahedral (Hex-) mesh (node based)

ANSYS Unstructured Hex/Tet mesh (node based and edge based formulations)

CFD/ Thermo-fluids

SC/Tetra Unstructured hybrid mesh (node based)

Fluent/CFX etc.

Unstructured hybrid mesh (cell based)

MHD HIMAG Unstructured hybrid mesh (cell based)

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 RELAP5-3DMELOCR

System representation code

Imprinting

AF

BC

ED

Merging

DAG-MCNP (UW)

Overcoming CAD discrepancy (e.g. overlapping) is common source of difficulty for MCNP

• Adopting one numerical technique for all simulations in ISPC can limit the size of the problem and is undesirable.

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A multi-disciplinary effort

Verification & Validation

Material database/Constitutive equations/ Irradiation effect

CAD- Geometry

Mesh services Adaptive mesh/mesh refinement

Visualization Data Management: Interpolation Neutral format

Time step control for transient analysis

Partitioning Parallelism

Neutronics Radiation damage rates

Thermo-fluid

Species (e.g. T2) transport

Electro-magneticsMHD

Coupled effect

Special module

RadioactivityTransmutation

Safety

e.g. source

Structure/thermo-mechanics

• 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

• Maintain consistency in the geometric representation among the analysis codes

• The CAD-based solid model is the common element across physical disciplines

specialized user FUNction

Data Mapping Script

CAD ModelNeutronics

Thermo-fluid & LM MHD

Electromagnetics

DMS

FW/Plasma Facing Surface Phenomena

DMS

DMS

FUN

Specialized physics models

FUN

Neutron source profile

q”

FW/PFC Thermo-fluid

profile

Stress/Deformation-Analysis

Species Transport

3-D design iterative assessment important

Safety or Transient events

FUN

*

*Structural Support

ISPC Design Process Flow

Tremendous work for ITER FW/SB at SNL

q

12

Jet impingement

He inlet

He outlet

Need experimental data for code verification & validation

Verification/validation needed on integration methodTemperature and He flow

characteristics under 10 MW/m2

“How to” incorporate a bigger resource into ISPC?

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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)

“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.---”

Nuclear Energy Innovation Hub

Advanced computational tools are continuously being developed in various projects:SciDAC, ITAPS, CCA, etc.

• Look for synergism• Not re-inventing the wheel but riding on state-of-the-art methodology

Next StepsHow do you see this moving forward?

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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 commitmentNear 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

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Plasma

Tro

idal

coi

l

Divertor

First wall/Blanket

6.2m

Test Blanket Module(TBM)

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

• 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.

Imagine if critical performance parameters can be projected and examined in advance----