Large eddy simulation of triboelectric charging in pneumatic powder transport

The triboelectric charging of powders and hoses during pneumatic transport can cause hazardous spark discharges. In this work we employ numerical simulations to gain a deeper understanding in the physical processes involved in the build-up of electrostatic charge. To this end, Large Eddy Simulations are performed to simulate the turbulent flow of the gaseous phase while the particulate phase is described in Lagrangian framework. Dynamic models accounting for the particle-wall and particle-particle charge exchange are implemented and a model describing the charge distribution in an insulating hose is also developed. Our numerical results are in good agreement with available experimental data, while our simulations provide additional physical insight and information about the charging process. The results presented herein can be used to improve the safety of operation of many pneumatic components in process engineering