Modelling of Gas-Solid Flows with Tribocharging

It has been known for centuries that materials tend to charge electrically when they come into mechanical contact. This charging, known as triboelectric charging, or tribocharging for short, is observed naturally in the large electric fields observed in dust devils and sand storms as well as in everyday circumstances, such as the tendency of air balloons to stick to hair or sweaters upon rubbing against them. Triboelectric charging also has significant industrial implications. Tribocharging creates hazards and inefficiencies in many gas-solid flow systems, from conveying pipes to polymerization reactors. Gas-solid flow systems are used in almost every major industry, from energy and fuel production to chemicals and food production to pharmaceutical manufacturing. In all of these cases, the hydrodynamics of the gas-solid flows strongly influence the overall efficiency and safety of the system, and the hydrodynamics can be altered significantly by tribocharging and resulting electrodynamic forces. Currently, the connection between the macroscopic behaviour of gas-solid systems and tribocharging is poorly understood due to the complex nature of these flows and the lack of understanding of the triboelectric charging. Via computational modelling and experimentation, we intend to expose how these flows cause charge to build up on particles, and in turn, how the charge on particles affects the flow behaviours. These insights will inform industries which utilize gas-solid flows on how they can avoid hazards and inefficiencies associated with tribocharging, or even utilize this charging to their advantage.

Supervisor name: 
Dr. Ali Ozel
Supervisor and Deputy email addresses:
Project location: 
James Nasmyth Building, JN2.18