Life stages of wall-bounded decay of Taylor-Couette turbulence
arXiv:1704.07892 · doi:10.1103/PhysRevFluids.2.114601
Abstract
The decay of Taylor-Couette turbulence, i.e~the flow between two coaxial and independently rotating cylinders, is numerically studied by instantaneously stopping the forcing from an initially statistically stationary flow field at a Reynolds number of . The effect of wall-friction is analysed by comparing three separate cases, in which the cylinders are either suddenly made no-slip or stress-free. Different life stages are observed during the decay. In the first stage, the decay is dominated by large-scale rolls. Counterintuitively, when these rolls fade away, if the flow inertia is small a redistribution of energy occurs, the energy of the azimuthal velocity behaves non-monotonically: first decreasing by almost two orders of magnitude, and then increasing during the redistribution. The second stage is dominated by non-normal transient growth of perturbations in the axial (spanwise) direction. Once this mechanism is exhausted, the flow enters the final life stage, viscous decay, which is dominated by wall-friction. We show that this stage can be modeled by a one-dimensional heat equation, and that self-similar velocity profiles collapse onto the theoretical solution.
References in corpus (6)
- High Reynolds number Taylor-Couette turbulence
- Exploring the phase diagram of fully turbulent Taylor-Couette flow
- Universality of anisotropic fluctuations from numerical simulations of turbulent flows
- The effect of roll number on the statistics of turbulent Taylor-Couette flow
- Turbulent Taylor-Couette flow with stationary inner cylinder
- Self-similar decay of high Reynolds number Taylor-Couette turbulence