Numerical study of powder electrification during pneumatic transport

Details

Supervisors

Papalexandris, Miltiadis

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil en chimie et science des matériaux

Abstract

During pneumatic transport, powders often face to buildup of electrostatic charge on their surface due to the wall-collisions of the particles against the pipe. This phenomenon can lead to hazardous spark discharges and dust explosions that are unwanted implications. A strong interest on the subject exists to understand the way the powders charging occurs and to determine the parameters affecting it. In the literature, many experimental studies and numerical investigations have been made. They concluded that the contact electrification depends on several parameters, as for example the transport regime, the materials of the pipe and the powder, the temperature, etc. Because of that, the ability of experiment to be reproducible is weak. Another conclusion is the strong link between the conveying conditions and the electrification of the powder. The development of the field of Computational Fluid Dynamics made the numerical simulations a helpful tool to model the flow and also the interaction with the powder. The purpose of this master thesis is to understand how the electrification of the powder is affected by the following parameters : the particles diameter, the particles mass flow rate inside the pipe, the particles material and finally the fluid velocity. The results of these simulations were analyzed to understand the role of the powder size, the physical properties and the converging air velocity on the triboelectric-charging. These results were compared with experiments found in the literature to verify the good prediction of the numerical model.