Imperial College London
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Professor Jan Cilliers

Faculty of Engineering, Department of Earth Science & Engineering

Chair in Mineral Processing
 
 
 
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Contact

 

+44 (0)20 7594 7360j.j.cilliers

 
 
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Location

 

RSM 1.46BRoyal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Cruise:2022:1361-6463/ac5081,
author = {Cruise, RD and Hadler, K and Starr, SO and Cilliers, JJ},
doi = {1361-6463/ac5081},
journal = {Journal of Physics D: Applied Physics},
pages = {1--14},
title = {The effect of particle size and relative humidity on triboelectric charge saturation},
url = {http://dx.doi.org/10.1088/1361-6463/ac5081},
volume = {55},
year = {2022}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Triboelectric charging is present in numerous technologies and everyday processes, providing both problems and opportunities. Despite this, there is no generalised model for the amount of charge that will build up on surfaces in contact. Here, we develop a new model for the saturation charge on triboelectrically charged spherical insulators, accounting for both equalisation of surface potentials and electrical breakdown of the surrounding medium. Experiments are conducted under controlled temperature and humidity using two independent methods, measuring the saturation charge on polymer spheres contacting grounded stainless steel. The results verify our equalisation of surface potentials model which describes how saturation charge density increases for smaller particle sizes. Key triboelectric properties are calculated: The estimated saturation charge on a flat surface and the equalisation potential between different materials, which can be used to predict charge saturation and quantify a triboelectric series. The transition radius below which electrical breakdown will cause saturation of charge is also calculated theoretically. Limitations to the model are demonstrated experimentally. As particle size reduces, a point is reached at which the electrostatic adhesion of particles to the grounded charging surface prevents further charge build-up. Furthermore, it is found that the saturation charge for smaller particles in humid conditions is greatly reduced. These calculations, and the demonstrated procedure, can serve as a tool for the design of technologies and processes influenced by triboelectric charge build-up, including triboelectric nanogenerators and electrostatic mineral separators.
AU  - Cruise,RD
AU  - Hadler,K
AU  - Starr,SO
AU  - Cilliers,JJ
DO  - 1361-6463/ac5081
EP  - 14
PY  - 2022///
SN  - 0022-3727
SP  - 1
TI  - The effect of particle size and relative humidity on triboelectric charge saturation
T2  - Journal of Physics D: Applied Physics
UR  - http://dx.doi.org/10.1088/1361-6463/ac5081
UR  - https://iopscience.iop.org/article/10.1088/1361-6463/ac5081
UR  - http://hdl.handle.net/10044/1/94470
VL  - 55
ER  -
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