Volume 8, Issue 2 p. 266-271

Transport characteristics of suspensions: Part IV. Friction loss of concentrated-flocculated suspensions in turbulent flow

David G. Thomas

David G. Thomas

Cambridge University, Cambridge, England

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First published: May 1962
Citations: 33


Turbulent flow friction factors were determined for flocculated suspensions of thoria, kaolin, and titania in tubes 1/8- to 1-in. diameter. The non-Newtonian laminar flow data were arbitrarily fitted with the Bingham plastic model. With this model the range of yield stress values was 0.018 to 1.39 lb.f/sq. ft., with a maximum ratio of coefficient of rigidity to viscosity of suspending medium of 11.1. The volume fraction solids were varied from 0.042 to 0.23.

Two types of behavior were observed depending on the value of the yield stress. For yield values less than 0.5 lb.f/sq. ft. the turbulent friction factors were always less than those for Newtonian fluids but tended to approach the Newtonian values as the Reynolds number was increased. For yield values greater than 0.5 lb.f/sq. ft. the friction factors were again less than those for New-tonian fluids but tended to diverge from the Newtonian values as the Reynolds number was increased. Both sets of data were correlated with the Blasius relation with the coefficient and exponent given in terms of the laminar flow properties und the volume fraction solids.