Transition to turbulence in pipe flow
Abstract:
We here present an experimental investigation into the role and significance of
travelling wave transients in turbulent pipe flow.
Turbulent flows in the range of 2000<Re<4500 are investigated and different
criteria are employed to identify travelling wave transients. We investigate
azimuthal symmetries as well as axial periodicity and the dynamics of low speed
streaks.
Furthermore we provide evidence that turbulence has a finite lifetime and the
dynamics evolve around a chaotic saddle in phase space.