Global modeling of wall material migration following boronization in NSTX-U

•WallDYN has been applied to post-boronization surface impurity evolution in NSTX-U.•New model has been developed for WallDYN to handle spatially inhomogeneous films.•Empirical boron coverage model developed for NSTX-U.•Integrated model qualitatively reproduces surface evolution measurements.•Oxygen in NSTX-U primarily sourced from lower and upper passive plates, and lower private flux zone.