1. Lithium Vapor Box Divertor
Christopher Jagoe ‘18

3. Motivation Plasma in tokamak escapes along field lines
Heat flux greater than 20 GW/m2
Divertor plates wear out
Vapor box uses volumetric cooling
Goal: prevent efflux into main body
3 orders of magnitude greater than the surface of the sun

5. Approach Lithium is hot, expensive, and difficult
Water vapor mock-up experiment
Parallel development of code (OpenFOAM)
DSMC for rarefied gas conditions
Kn = mfp/L between 0.01 and 1

6. Scaling Water vapor in the 0º – 100º range
Range of pressure differences much lower
Box size will be smaller but not too small
Prevent ice from forming

7. Code Installing (harder than you think) blockMeshDict
Boundary conditions
Wall, zeroGradient, etc
Patching to allow for different densities
Courant number, mesh size affects run time

8. Results Shock pattern discovered
Ability to create a pressure driven flow
Capability to use more complex geometries
Post-processing in Paraview

11. Impact Next step: comparing code to water vapor
If successful, acquiring fundings for NSTX or MAST
Reactors can burn cheaper, faster, longer

12. References
Diagram on slide 3 from “The Lithium Vapor Box Divertor” by R. J. Goldston, R. Myers, J. Schwartz, Physica Scripta, 2016