• Corpus ID: 90249331

Background noise pushes azimuthal instabilities away from spinning states

  title={Background noise pushes azimuthal instabilities away from spinning states},
  author={Giulio Ghirardo and Francesco Gant},
  journal={arXiv: Fluid Dynamics},
Azimuthal instabilities occur in rotationally symmetric systems, either as spinning (rotating) waves or standing waves. We make use of a novel ansatz to derive a differential equation characterizing the state of these instabilities in terms of their amplitude, orientation, nature (standing/spinning) and temporal phase. For the first time we show how source terms determine quantitatively the system preference for spinning and/or standing states. In particular we find that, when present… 

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