76
2 Water at Rest and in Motion
comparing Eqs. (2.115) and (2.116), the friction factor f for the laminar flow
in a circular pipe becomes:
64
f = Re'
where Re = uD Iv.
(2.117)
The above equations can further be modified using the experimental results
to obtain (Schlichting, 1960):
1 _
(1/2)
jI/2 - 2.0loglO Re f
- 0.8,
(2.118)
which constitutes Prandtl's universal law of friction for smooth pipes.
In Part III we apply many of these results to the internal flows in marine
organisms. However, these results should be used with some caution as the
velocity distribution and friction formulas are based on closely packed sand
grain roughness. Such roughness is very different from that observed in the
internal flow of marine organisms.
2 Water at Rest and in Motion
comparing Eqs. (2.115) and (2.116), the friction factor f for the laminar flow
in a circular pipe becomes:
64
f = Re'
where Re = uD Iv.
(2.117)
The above equations can further be modified using the experimental results
to obtain (Schlichting, 1960):
1 _
(1/2)
jI/2 - 2.0loglO Re f
- 0.8,
(2.118)
which constitutes Prandtl's universal law of friction for smooth pipes.
In Part III we apply many of these results to the internal flows in marine
organisms. However, these results should be used with some caution as the
velocity distribution and friction formulas are based on closely packed sand
grain roughness. Such roughness is very different from that observed in the
internal flow of marine organisms.