Rotating Rayleigh-Benard convection: The Kueppers-Lortz transition.

摘要

Rayleigh-Benard convection with rotation about a vertical axis is investigated for small dimensionless rotation rates 0 < (Omega) < 50. The convection cell is cylindrical with aspect ratio (Gamma) = 10 and the convecting fluid is water with a Prandtl number of 6.8 at T = 23.8C. Comparisons are made between experimental data and linear stability theory for the onset Rayleigh number and for the wave number dependence of the convective pattern. The nonlinear Kueppers-Lortz transition is found to occur significantly below the theoretically expected rotation rate (Omega)(sub c) and to be nucleated by defects created at the lateral cell walls. 20 refs., 10 figs.