1. Toroidal Fusion Shielding Design Project
Final Presentation by:
Matt Franzi
Andrew Stach
Andrew Haefner
Ian Rittersdorf

2. Overview Fusion Power Goals Materials Design MCNP Simulations
Results and Analysis
Conclusions

3. Fusion Power
Fusing light nuclei together releases large amounts of energy
D + T = He4 + n MeV
Neutrons deposit energy in a lithium blanket
Important Li Reactions
6Li + n = 4He + T MeV
7Li + n = 4He + T – 2.5 MeV
Image courtesy of wikicommons

4. Goals Two primary concerns: Tritium production
Tritium breeding ratio = 6Li absorption per fusion neutron
Ideally keep this above unity
Energy deposition in the blanket

5. Materials Lithium Beryllium Stainless Steel 316L
Used for its tritium (fuel) production
Beryllium
Used for its reflective properties and (n,2n) reactions
Stainless Steel 316L
Used for its strength and ability to absorb neutrons

6. MCNP Approach Slab Model Toroidal Model Gave “ball park” figures
Material thicknesses
Material placements
Toroidal Model
Gives more realistic results

7. Final MCNP Model Toroidal Design ITER Size Boundaries
Major Radius = 6 m
Minor Radius = 2 m
Height = 6 m

8. Model Cross-Section

9. Neutron Multiplication
I also tend toward more boring info on formal slides but I really like how you portrayed these… try using as conclusions perhaps?
N multiplication
-energetic reactions from neutrons
(the Be reaction that gives off a lot of E and the 4.86 MeV Li-6 reaction)
Then conclude with
More neutrons=more power
Capitalize on (n,2n) reaction then maybe list a few materials?
Neutron Multiplication
More Neutrons = More Power = More $$
Find a way to produce more neutrons
Layers of Neutron Multipliers
Capitalize on the (n, 2n) reaction
Lead
Beryllium

10. Multiplication Layers
Sheets of non-lithium material
Absorbs a higher energy neutron
Produces two neutrons of lower energies
Is this trade off worth it?
Lithum-6 reaction with thermal neutron produces 4.8 MeV

11. Multiplication Layer Design
Symbiotic relationship between beryllium and lithium
Complimentary neutron cross-sections
Beryllium has 2-3 barns at energies of 2-14 MeV
Lithium has barns at energies under 2 MeV
Sandwich layers of beryllium between layers of lithium
Lithium acts as a high pass filter
Beryllium acts as a low pass filter and creates lower energy neutrons

12. Multiplication Layer Model

13. Mutli-Layer Method
Start with the analytic calcs of mean free paths for Pb and Be perhaps?
Maybe refer back to the threshold energies and Q values
Explain why Be was hypothesized to be the best
Maybe put in our old graphic of the Pb and Be cross section

14. Maximization of both TBR and E/Eo pro
Explain matrix and method to our madness
Explain why they both sort of go hand in hand up to a point

15. Matrix results and graphs
Explain why we are sweet

16. Talk about escaping particles
Energy that is leaving our system
Explain why we are getting the results we did (IE where and why we are depositing energy)
Somewhere we should talk about all the Li-6 reactions and say that T production is the most prominent

17. Talk about what assumptions we made in making the reactor
Talked about the tungsten here
Maybe compare our ideal results to the results with varying levels of tungsten