Simulation of PMMA powder flow electrification using a new charging model based on single-particle experiments

Thus far, simulations fail to predict the electrostatic charging of powder during pneumatic transport accurately. 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 measured powder charging of in our pneumatic conveying test rig and compared it to the simulations. The simulations and the new model successfully predict the charging of powder consisting of monodisperse particles of a size of 200 μm. Contrary to the usual procedure for this type of simulation, the numerical predictions require no tuning of any model parameters. According to our model, these contacts lead to bipolar charge distributions.