  Thus far, simulations have failed to predict accurately electrostatic powder
charging during pneumatic transport. We advanced the modeling of powder flow
charging by a three-part study: first, we shot individual particles on a metal
target and measured the exchanged charge. Second, based on these results, we
formulated an empirical model and implemented it in our CFD tool. Using this
tool, we performed large-eddy simulations of the powder flow through a square
duct with a cylindrical obstacle inside. Finally, we compared the simulations
to measurements in our pneumatic conveying test rig. The simulations
successfully predicted the charging of powder consisting of monodisperse
particles of a size of 200 $\mu$m. Contrary to the usual procedure for this
type of simulation, the tool requires no tuning of any parameters. According to
our simulations, the powder mostly charged when hitting the cylindrical
obstacle. The contacts led to bipolar charge distributions.
