1. ITER Tritium Fuel Cycle Modeling
Scott Willms and Bill Kubic
Los Alamos National Laboratory
Fusion Nuclear Science and Technology Workshop
UCLA
August 2, 2010

2. Outline Tritium Processing modeling history TEP modeling
Consideration of next steps

3. Tritium processing modeling history

4. Simplified ITER flow diagram

5. Example fusion fuel cycle modeling efforts
Code
Period
Code Base
Institution(s)
Type of code
Purpose
TBR-related FC model
Mid 1980’s
Custom
UCLA
High-level, first-order differential equations
Estimate required TBR
Supercode
Late 1980’s
ANL, LANL
Scaling laws
Cost and overall size
TSTA Model
LANL
Algebraic flow and reaction equations
Pressure/flow control
Dynsim
1980’s-1990’s
LANL-Japan
Rigorous ISS
ISS understanding and design
CFTSIM
1990’s
CFFTP
TRUFFLES
UCLA-LANL
High-level, modular fuel cycle
T inventory, FC design
TRIMO
1990’s-2000’s
CFFTP-UCLA-ITER-FZK
T inventory, FC design (ITER)
ITER TEP
Commercial
LANL-SRNL
Medium-level, modular systems code
TEP design

6. Uses for tritium processing models
Component design
System design
Parameter regression
Technology trade-off studies
Hazard characterization and analysis
Requirements determination
Control system development
Experimental development augmentation
Design documentation
Operator training

7. ITER TEP modeling

8. TEP process flow diagram

9. TEP modeling overview TEP model used for: TEP models include:
Component regression from experimental data
Technology selection
Component sizing
TEP models include:
Component models
Detailed understanding of component performance
System models
Overall process performance

10. Modeling tools relationship
Aspen Plus
Kinetic model data
Aspen property library
Basic flowsheet data
User defined model
Aspen Custom Modeler
Steady state model
Aspen Dynamics library
Custom TEP library
Aspen Dynamics
Dynamic model

11. TEP models completed Modules Sub-Systems Permeator (ACM) PMR (ACM)
PERMCAT (stand-alone)
Vacuum Pumps (ACM)
Ambient molecular sieve bed (ACM)
Cryogenic molecular sieve bed (ACM)
Dynamic feed generator (ACM)
Molecular and transition flow conductance model (ACM)
Sub-Systems
Hydrogen-like processing
Air-like processing
Water-like processing

12. Examples of module bechmarks
Comparison of permeator model with data of Willms et al. (1993)
Comparison the model with LANL data for a Normetex 15 backed by an MB-601

13. Aspen Model of Permeator / AMSB for HLP

14. Aspen Model of Combined ALP-WLP14

15. Aspen system models used to optimize design
Can account for system interactions in the design process
Permeator-pump interactions
PMR-pump interactions
Multistage permeator pump performance
Easy to modify PFD to reduce equipment sizes and minimize pumping requirements
Can base sizing calculations on overall system performance

16. Example - Permeator Optimization
Vary the number of first stage pumps
Determine tritium release from third (final) stage peremator
Determine breakthrough area
Determine number of pumps and permeator area based on point of dimishing returns
Six MB-601 pumps for first stage
3 m3 of membrane area for first stage
Evaluate system margin
Margin based on overall system performance and not individual units
Tritium release from third stage as a function of number of first stage pumps
First stage area as a function of number of first stage pumps
Most Common Operations
Permeator Train Breakthrough
Tritium release from third stage as a function of feed rate

17. Consideration of next steps

18. DT
Major flow paths for ITER Fuel Cycle during DT

19. Next steps
Past modeling efforts have laid an excellent foundation for the next work that needs to be performed
The ITER TEP modeling effort has laid an excellent template for future work
Major development needed includes:
Models of ITER sub-systems (expect for TEP)
ITER Fuel Cycle model
ITER TBM modeling
Fusion Nuclear Science Facility model
Benchmarking

20. Summary
Computer modeling has been an important component of tritium processing development
Recent ITER TEP modeling was not only successful in itself, but lays an excellent template for future modeling work
There are a number of current and future projects which would benefit greatly from further modeling work