Evaluation of the parameters influencing electrostatic charging of powder in a pipe flow

• The electrostatic charging of powders during pneumatic transport is assessed numerically.
• Large Eddy simulations including dynamic charge exchange models were performed.
• The influence of design parameters on the charge was evaluated using a Design of Experiments.
• The conveying air velocity showed to increase the powder charge significantly.
• An increase of the pipe diameter and particle mass flow rate decreases the charge.

Triboelectric charging of powders during pneumatic transport can lead to hazardous spark discharges. In this study, the charging process was studied numerically by means of large eddy simulations. A range of design parameters was then analyzed statistically applying the Design of Experiments methodology. It is shown that the electric charge of the powder can be significantly decreased by reducing the conveying air velocity. Furthermore, the usage of pipes of a larger diameter and the application of higher solid mass flow rates also reduce the powder charge.