1. UEDGE Points of Investigation: Needs of a scalable preconditioner
How is convergence affected by …
Access to the exact Jacobian via coloring?
Adding neutral gas terms?
Decreasing the time step?
The method of domain partitioning?
The answers have improved our results from the solid lines to the dashed lines

2. UEDGE Investigation Results: Designing a scalable preconditioner
Exploiting the exact Jacobian via coloring
ASM is now a viable (scalable) solver
What effect do neutral gases play?
Neutral gases often demand a direct solver
Choosing a reasonable time step?
ASM converges scalably for Δt≈10-4
1D vs. 2D domain decomposition
Without neutrals, 1D is preferred
Our PCFieldSplit solves the neutral terms with LU and other terms with ASM.
Scalability LU FS
4.82
7.98