Minimum description of the onset of pipe turbulence*
Philipps-Universität, Renthof 6, 35032 Marburg, Germany
Published online: 15 May 1999
To demonstrate essentials of the mechanism for the onset of turbulence in a pipe at Re=2000, 48 degrees of freedom are enough. The derivation from the Navier-Stokes equation uses a novel type of modes which guarantee linear stability. For the reduction of the nonlinear interactions, the modes are grouped in 3 blocks. Facilitated by these simplifications the interdependence between linear and nonlinear processes is analysed, however, just for a special example. A phenomenon resembling backflow is identified.
PACS: 47.27.Cn – Transition to turbulence / 47.20.Ft – Instability of shear flows / 47.11.+j – Computational methods in fluid dynamics
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1999