1. The Gas Dynamic Trap (GDT) Neutron Source
Fusion Nuclear Sci. and Tech. Meeting
UCLA, August 2-6, 2010
Budker Institute of Nuclear Physics Novosibirsk, Russia
Tom Simonen, University of California Berkeley

2. Objective
Employ A Simple DT 14 MeV Neutron Source to Test / Validate Materials &Subcomponents
Utilize International Leverage
Provide IFE Synergy
gas Dynamic Trap DT Neutron Source = DTNS

3. DTNS General Attributes
High Neutron Flux (2 MW/m2)
Low Fusion Power (2 MW)
Uniform Radiated Area (1 m2)
Steady State (for Weeks)
Low Tritium Consumption (0.15 kg/FPY)
Dirt Simple Physics (Te is main concern)
Technology Needs (Steady State 80 keV Neutral Beams and Tritium Reprocessing)

4. Main Points of This Talk
The Russian GDT Concept is a Near-Term DT Neutron Source (DTNS) for Material and Subcomponent Testing and Qualification
The Physics Issues can be Addressed in GDT
DTNS Same Size and Gyro-Radius as GDT
Conceptual Designs have been Carried Out
Russia, Germany, Sweden, USA
Urged Action: US-Russia GDT Collaboration

5. Comparison of Neutron Sources
ADS
DTNS
Tokamak
Flux (MW/m2) 2
14 MeV DT Neutrons No
Yes
Test Area (m2)
0.01 1
100
Blanket Test?
Sub-modules
Tritium/FPY (kG)
0.1 10
Requires Breeding?

6. 1980’s Mirror Based Neutron Source Designs
TDF

7. 1980’s Mirror Neutron Source Designs
Based on Unproven Theoretical Concepts
Required Complex Minimum-B Magnets
Required Complex Thermal Barriers
Valuable Conceptual Design Studies Carried Out by Industry, Labs, and Universities

8. GDT Axisymmetic Mirror Concept Novosibirsk, Madison, Kyoto
Circular Coils without Thermal Barriers
Simplified Engineering and Physics
No neoclassical radial transport
High mirror ratio and Natural Divertor
Ease of Construction and Maintenance

9. 2010 GDT Neutron Source Concept
Based on GDT Experimental Data (60% Beta)
Axisymmetric Stabilized with ExB Shear Vortex
Classical Theoretical Foundation
Electron Drag & Collisional Warm Plasma
Sloshing Ions provide Micro-Stability (TMX-U)
Extrapolation to 80 keV NBI and 1.5 T Field
No Change in size or gyro-radius

10. DT Neutron Source Parameters
Length 7 meters
Magnetic Field 1.5 Tesla
Mirror Ratio >10
Neutral Beam 80 keV, 20 to 40 MW
Mean Ion Energy 40 keV
Electron Temp keV
Density 4 e20 /m3
Same Size and Gyro-radius as the GDT Device

11. GDT Device in Novosibirsk Russia Most Active Russian Experiment 18 meters Long11

12. GDT Experiment Layout

13. GDT Beta = 60% Vortex Shear Flow MHD “Stabilization” A. D
GDT Beta = 60% Vortex Shear Flow MHD “Stabilization” A.D. Beklemishev, Fus. Sci. & Tech. May 2010
U = 150 В
U = 0
Simulated
flow lines

14. GDT DD-Neutron Axial Profile (Agrees with Computer Simulation)

15. Monte-Carlo Simulation of the GDT Fast Ion Energy Distribution (No Significant Loss Cone to Drive MicroInstabilities)

16. Н0 – beams, Н – plasma, a=14 cm, R = 33.
Te vs heat power: experiment and calculations
Н0 – beams, Н – plasma, a=14 cm, R = 33.
calculation
Te ~ Ph2/3
experiment
Te, eV
calculation
Te ~ Ph2/7
Ph, MW
P.Bagryansky, The 8th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 16

17. Neutron Flux Increases With Te (for various NBI energies) Today’s Te ~ 0.25 keV would produce ~ 0.4 MW/m2

18. A Russian Neutron Source Design A MW of Fusion Power for Weeks Neutron Flux ~ 2 MW/m2 Test Area ~ 1 m2

19. GDT-NS Magnet Design Bobouch et. al. Fusion Science & Tech
GDT-NS Magnet Design Bobouch et. al. Fusion Science & Tech. v41, 2002, p44 Frascati, Novosibirsk, Snezhinsk,…

20. DTNS Would Produce ITER-Like Neutron Energy Spectra (Fischer, A
DTNS Would Produce ITER-Like Neutron Energy Spectra (Fischer, A.Moslang, A.Ivanov, FE&D 48 (2000) p.307)

21. Material Sample Test Assembly (Holds ~8,000 Temp
Material Sample Test Assembly (Holds ~8,000 Temp. Controlled Specimens) U. Fisher, A. Moslang, A.A. Ivanov, FE&D 48 (2000) p307

22. Conclusions GDT Leads to a Fusion Neutron Source
For Material and Subcomponent Qualification
Based on Classical Theory (60% Beta)
Physics Issues can be Addressed in GDT
Te, MHD. Micro-stability
Attractive Conceptual Designs Carried Out
Russia, Germany, Sweden, USA
Your Support for a ICC-Level GDT US-Russia Collaboration is Solicited

23. References
“Gas dynamic trap as high power 14 MeV neutron source”, P.A Bagryansky , et. al. Fusion Engineering and Design 70 (2004), p
Assessment of the gas dynamic trap mirror facility as intense neutron source for fusion material test irradiations”, U. Fischer, A. Moslang, A.A. Ivanov, Fusion Engineering and Design, 48 (2000) p

24. GDT Classical Confinement Scaling
Tau sub E hot ~ Te^3/2 / ne
Tau sub E warm ~ RL / vi ~ RL / Te^1/2
Te ~ beta B^2 R L all to the 1/3