  An integrated modeling framework for investigating the application of solid
boron powder injection for real-time surface conditioning of plasma-facing
components in tokamak environments is presented. Utilizing the DIII-D impurity
powder dropper setup, this study simulates B powder injection scenarios ranging
from mg to tens of mg per second, corresponding to boron flux rates of
$10^{20}-10^{21}$ B/s in standard L-mode conditions. The comprehensive modeling
approach combines EMC3-EIRENE for simulating the plasma background and DIS for
the ablation and transport of the boron powder particles. The results show
substantial transport of B to the inboard lower divertor, predominantly
influenced by the main ion plasma flow. The powder particle size (5-250 $\mu$m)
was found to be insignificant for the scenario considered. The effects of
erosion and redeposition were considered to reconcile the discrepancies with
experimental observations, which saw substantial deposition on the outer PFCs.
For this purpose, the WallDYN3D code was updated to include B sources within
the plasma domain and integrated into the modeling framework. The
mixed-material migration modeling shows evolving boron deposition patterns,
suggesting the formation of mixed B-C layers or predominantly B coverage
depending on the powder mass flow rate. While the modeling outcomes at lower B
injection rates tend to align with experimental observations, the prediction of
near-pure B layers at higher rates has yet to be experimentally verified in the
carbon environment of the DIII-D tokamak. The extensive reach of B layers found
in the modeling suggests the need for modeling that encompasses the entire wall
geometry for more accurate experimental correlations. This integrated approach
sets a precedent for analyzing and applying real-time in-situ boron coating
techniques in advanced tokamak scenarios, potentially extendable to ITER.
