IFE Target Collaboration Discussion

​

​

General Atomics Proprietary Information

By

Dr. Neil Alexander

Senior Scientist

Presented to

IFE Industry Day 2

LLNL

November 10, 2022

General Atomics Proprietary Information

General Atomics Proprietary Information

1

Are there target related areas that can form the basis of a large collaboration (Hub)?

• Is a large collaboration or HUB for targets or related technologies desired?

​

1. What specific technologies do we want to collaborate on in a hub?
1. What would be the demonstration goals for these technologies?
2. What operating model makes sense for a targets hub(s)
• Common facilities / test stands
• Joint demonstration of a technology(ies)
• Shared knowledge and practices
• Combination, other?
3. Who would participate and in what way (people, technology, etc)?

The goal of this discussion is to start to create a compelling vision, strongly supported by the community, for federal program managers, senior lab management and industry to advocate for public funding to make the hubs real.

Existing DOE Hubs:

• The Consortium For Advanced Simulation of Light Water Reactors (casl.gov/)
• Joint Center for Artificial Photosynthesis (solarfuelshub.org/)
• Joint Center for Energy Storage Research (jcesr.org)
• Critical Materials Institute (ameslab.gov/cmi)
• National Alliance for Water Innovation (nawihub.org)

These hubs funded by DOE at $75M to $122M for 5 years; plus some private cost share

2

General Atomics Proprietary Information

2

Key IFE technology development needs

• A high gain target demonstrated
• An affordable driver
• Affordable, mass production of targets
• 86.4K to 864K targets per day per reactor (1 to 10 Hz)
• A Target injector
• Demonstration of accurately hitting target on-the-fly
• Demonstration of cryo-target survival to reactor chamber thermal threat
• Chamber reset/target waste removal
• Final optics protection
• A survivable first wall
• Radiation tolerant, low activation, structural materials (for chamber, …)
• Or rapid, convenient remote replacement of damaged materials/structures
• Long life Blanket for tritium breeding and heat extraction
• Tritium Processing Systems that can handle waste stream (HTO, CH3T, …)

​

​

This discussion

Fuel cycle/blankets/materials discussion

Lasers discussion

3

General Atomics Proprietary Information

3

Large collaboration may be more appealing in pre-precompetitive areas

Basic Science and properties

Engineering practice and protocols

Production lines for particular targets

Company specific target designs

Manufacturing methodologies

More Core IP

Less Core IP

Pre-competitive areas

4

General Atomics Proprietary Information

4

Limited resources are a potential reason to enter into larger collaboration

• Much must be developed and demonstrated
• Resources are limited
• $, personnel, time, supplies, facilities

⇒

Pooled resources to collaborate on some key needs can advance IFE case for all

- Likely not in core IP

Core IP likely different for each institution

Hub of many vs 1 to1 relationships

5

General Atomics Proprietary Information

5

Ideas for collaboration 1: Cryogenic materials properties measurement

• DT targets will be cryogenic
• Properties unknown for some potential target materials
• Cryogenic (~19K) to room temperature (300K)
• Polymer foam shells, FLiBe, Pb:Li alloy, new thin films
• K, Cp, LTE, E, tensile strength
• DT effects in DT wetted foam shells
• Fast filling and layering wetted foam capsules can greatly lower tritium inventory
• <~40 – 100 X less than permeation with beta-layering)
• Wetted foams LDD target more thermally robust (survivable) than solid DT layer LDD target
• Facilities – equipment for cryogenic materials property testing

​

6

General Atomics Proprietary Information

6

Ideas for collaboration 2: Dealing with fueling and layering targets

• Developing equipment for cryogenic dispensing and handling of liquid DT/D2
• Studies of DT/D2 wicking into foam capsules
• How fast
• Precision fills
• Measure thermal response of DT/D2 wetted foam to reactor thermal threat
• Does target survive intact?

A DT users facility to test target fill and layering equipment ala TSTA could be of interest

Facility for generation of post-shot chamber hot gas/plasma

-Determine heat loadings on cryo materials

-Target survival

7

General Atomics Proprietary Information

7

Ideas for collaboration 3: Demonstration of accurate target engagement

• Has been done with low speed (5 m/s) target with small beam <Φ1/2”
• Want at high speed (~50 to 200 m/s) with large beam (~Φ1m), ideally full power
• Need large aperture beam steering
• Need tracking integrated with laser and steering
• Launch of target or surrogate target
• Demonstration in one concept reduces skepticism for all

Seed & Alignment lasers

AOM

Deflection

Amp

Compression and conversion

Transverse tracking camera

Glint Laser

Transverse Laser

Target Injector

Crossing Sensors

Retro-reflector

Camera/Coincidence

Grazing incidence metal mirror (GIMM)

Target Chamber

Length 1-2 m

8

General Atomics Proprietary Information

8

Precise, rapid, laser engagement is at the heart of EUV lithography exposure systems

Extreme Ultra-violet (EUV)

lithography system

EUV shoots 30 µm

tin targets @ 50kHz

9

General Atomics Proprietary Information

9

Ideas for collaboration 4: Technologies for target fabrication

• Target characterization is a key to making quality targets
• High yield and or reject defects
• Target rejection systems
• Detection of defective targets coupled to mechanics to remove rejects
• For manufacturing processes with a distribution of outputs exceeding target spec.s
• Fast handling of delicate, light-weight targets
• Static control
• Positive grasp and release
• Non-contact methods
• High speed additive manufacturing
• High speed, cure on command (e.g. UV) polymer foam system development
• Other target parts or techniques: …

Enough commonality to warrant?

Bad potato chips removed via optical detection and air puffs

TOMRA

10

General Atomics Proprietary Information

10

Ideas for collaboration 5: Co-development of target injectors

• Tech: Gas Gun, electromagnetic, or other
• Rapid loading
• Cryogenic
• In compatible gases, if present, removed before chamber
• Differential pumping on flight path
• Sabot separation (if used)
• Sabot recycle and or reuse
• Neutron shutter
• Long life

Potential Specifications:

• ~50 – 200 m/s,
• using ≤ ~1000g acceleration
• accuracy better than ~0.5 mrad

Saddle coils for spin

Axial coils for linear acceleration

Deceleration coil

Deflection coil

Spherical Target

Cylindrical Target

Cone-in-Shell Target

Gas gun launched

Potentially sabots can adapt one type of injector to multiple types of targets or minor changes in target shape

Gas gun 400 m/s

Linear Induction Accelerator 57 m/s

Prior Injectors (single shot, room temperature) accuracy

• Gas gun 0.59 mrad at 400 m/s
• Gas gun 0.24 mrad at 50 m/s
• Induction accelerator 0.14 mrad at 57 m/s

11

General Atomics Proprietary Information

11

Ideas for collaboration 6: Safety, Rad Waste, Material Supply

• We are straying into the Blankets/Materials HUB discussion since
• Targets are a primary material consumable for reactors
• Convenient if targets use liquid wall materials where possible
• Common methodology for accessing tritium safety for reactor
• Target contains tritium
• Tritium safety is one of the foremost IFE reactor safety issues
• Reducing tritium inventory will make reactors safer, more licensable, and easier to site
• Common methodology for accessing radioactive waste disposal ratings for target materials
• Working on potential supply chain issues for target materials
• High purity can be required to lower waste disposal ratings
• Bi impurity in Pb, U impurity in Be

12

General Atomics Proprietary Information

12

Your thoughts for target collaboration areas

Any suggestions?

Courtesy M. Campbell

Issues?

Concerns?

13

General Atomics Proprietary Information

13

Any takers for target “Hub” collaborations?

Specific Technologies to include?

- With what demonstration goals?

What operating model to use?

- Common facilities/test stands?

- Shared knowledge and practices?

- Joint demonstration of a technology?

- Combination?

- Other?

Who wants to participate?

-What can be brought (people, tech.,…)?

14

General Atomics Proprietary Information

14