  This paper presents a new theory of turbulence in time-independent
non-Newtonian fluids. The wall layer is modelled in terms of unsteady exchange
of viscous momentum between the wall and the main stream, following the classic
visualisation of inrush-sweep-ejection/burst. The thickness of the wall layer
is found to be the same for Newtonian and purely viscous non-Newtonian fluids,
when normalised with the instantaneous wall parameters at the onset of
bursting. The results indicate that the mechanisms of turbulence in Newtonian
and time-independent fluids are identical when structural similarity relations
in turbulence are based on phase-locked parameters linked with the development
of secondary flows rather than on time-averaged wall parameters. This
similarity analysis collapses the local critical instantaneous friction factor
data of both Newtonian and non-Newtonian fluids at the point of bursting into a
single curve. The method greatly simplifies the analysis of turbulent transport
phenomena in non-Newtonian fluids.
  Keywords: Turbulence, time-independent non-Newtonian, Power law, pipe flow,
wall layer
