• Model for modulated and chaotic waves in zero-Prandtl-number rotating convection

    • Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/pram/071/03/0545-0557

    • Keywords

       

      Rayleigh–Bénard convection; dynamical systems; modulated convection; chaos.

    • Abstract

       

      The effects of time-periodic forcing in a few-mode model for zero-Prandtl-number convection with rigid body rotation is investigated. The time-periodic modulation of the rotation rate about the vertical axis and gravity modulation are considered separately. In the presence of periodic variation of the rotation rate, the model shows modulated waves with a band of frequencies. The increase in the external forcing amplitude widens the frequency band of the modulated waves, which ultimately leads to temporally chaotic waves. The gravity modulation, on the other hand, with small frequencies, destroys the quasiperiodic waves at the onset and leads to chaos through intermittency. The spectral power density shows more power to a band of frequencies in the case of periodic modulation of the rotation rate. In the case of externally imposed vertical vibration, the spectral density has more power at lower frequencies. The two types of forcing show different routes to chaos.

    • Author Affiliations

       

      Alaka Das1 Krishna Kumar2

      1. Department of Mathematics, Jadavpur University, Kolkata 700 032, India
      2. Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur 721 302, India
    • Dates

       
  • Pramana – Journal of Physics | News

© 2017 Indian Academy of Sciences, Bengaluru.