• Molecular-Diffusive Effects in Penetrative Convection

      Fernando, H. J.S.; Little, Leigh J.; Arizona State University; The College at Brockport (1990-09-01)
      An experimental study was performed to investigate the influence of molecular diffusion on turbulent entrainment during penetrative convection. The entrainment coefficient E was determined as a function of the Richardson number Ri and Peclet number Pe. It appears that, in parameter ranges 65
    • Transient, Non-Axisymmetric Modes in Instability of Unsteady Circular Couette Flow

      Neitzel, G. P.; Kirkconnell, C. S.; Little, Leigh J.; Georgia Institute of Technology; The College at Brockport (1995-02-01)
      Laboratory and numerical experiments were conducted to quantitatively determine the modal structure of transient, nonaxisymmetric modes observed during the instability of an impulsively initiated circular?Couette flow. The instability develops initially as an axisymmetric, Görtler?vortex state and persists ultimately as a steady, axisymmetric Taylor?vortex state of different wavelength. The transition between these two states results from the instability of the Görtler mode combined with the underlying developing swirl flow and is dominated by nonaxisymmetric modes. The laboratory experiments employed flow visualization coupled with digital video and image?processing techniques; numerical experiments were performed using the spectral?element code,