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II.—The Effect of Concentration on the Terminal Fall Velocity of Particles in Suspension*

Published online by Cambridge University Press:  14 February 2012

Hugh Rankin Thorpe
Hugh Rankin Thorpe
Affiliation:
formerly Research Student, University of Aberdeen.
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Synopsis

The paper describes an investigation of the terminal velocity of uniformly dispersed particles of various shapes, sizes and densities falling through water.

It is concluded that for concentrations above 0–5 per cent by weight, the suspension as a whole behaves as though it were viscous even though the individual particles lie well outside the Stokes range. The shape of the particles has a significant effect only when the concentration is less than 0·5 per cent, and for concentrations between 0·5 and 7·0 per cent, the relative changes in velocity of descent are adequately described for a range of particle shapes from highly angular to spherical and for sizes at least up to 0·65 mm. nominal diameter, by the power series

in which U is the velocity of the suspension, U0 that of a single particle, d the nominal diameter (i.e. that of a sphere having the same volume) and s the mean spacing of the particles.

If the concentration is lower than 4 per cent, the equation may be assumed linear in (d/s) without serious error.

Type
Research Article
Information
Proceedings of the Royal Society of Edinburgh Section A: Mathematics , Volume 67 , Issue 1 , 1965 , pp. 9 - 24
Copyright
Copyright © Royal Society of Edinburgh 1963

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References

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