the effect of the particle size distribution on non-newtonian turbulent ...

Chapter 2 Literature Review Page 2.30
The two constants a and b were assumed to be identical to those evaluated by Clapp (1961)
and hence taken to be:
3,8
a =-,
n
and
b = 2,78.
n
(2.54)
(2.55)
For rough walled pipes <strong>the</strong> velocity pr<strong>of</strong>ile was modified using Prandtl's assumption that
u(y) ex y/k and <strong>the</strong> constants re-evaluated using <strong>the</strong> Newtonian data <strong>of</strong> Nikuradse (1933).
The relationship for rough wall pipes is:
JT
- -- -2,5 1 og [Re] -
f n k
_ 3,75 + 8,5 .
n
The Reynolds number formulation as given by Torrance is:
(2.56)
(2.57)
The Torrance model is unable to predict <strong>the</strong> onset <strong>of</strong> turbulence (as shown by Slatter, 1994)
and thus it was assumed (Mun, 1988) that <strong>the</strong> transition occurs at <strong>the</strong> intersection <strong>of</strong> <strong>the</strong>
laminar and turbulent curves.
2.11.3 The Kemblowski & Kolodziejski Model
Kemblowski & Kolodziejski (1973) developed an empirical equation <strong>of</strong> <strong>the</strong> Blasius type to
predict <strong>the</strong> behaviour <strong>of</strong> power law fluids. Tests undertaken related <strong>the</strong> flow resistances <strong>of</strong>
10%,20%,30%,40% and 50% by weight aqueous suspensions <strong>of</strong>kaolin in pipes <strong>of</strong>circular
cross-section. The test results are given in <strong>the</strong> form <strong>of</strong> <strong>the</strong> dependence <strong>of</strong> <strong>the</strong> coefficient <strong>of</strong>
flow resistance on <strong>the</strong> generalized Reynolds number