The role of particle properties on powder electrification during pneumatic transport

During pneumatic transport, powders often accumulate electrostatic charge due to collisions of the particles with the walls of the pipe, which may cause hazardous spark discharges. For this reason, there is a strong interest in studying various options to constrain the electrification process. In this talk we present results of numerical simulations that we performed in order to evaluate the influence of certain key particle properties to the build-up of charge. In our study, the particle-laden turbulent flow is treated numerically via Large Eddy Simulations (LES), while the motion of each particle is tracked in Langrangian framework, assuming four-way coupling between particles and carrier gas. Further, the governing equations are supplemented with dynamic models accounting for the particle-wall and particle-particle charge exchange. In our presentation we discuss results of the parametric studies with respect to the particle diameter, density and elastic properties of the powder. Our talk concludes with the results of a parametric study with respect to the flow rates of the carrier gas and the powder.