Convection in a rotating cylindrical annulus with azimuthally non-uniform heating

Abstract

Abstract The paper reports a study of the influence of azimuthally non-uniform heating on the regimes of convective flows in the rotating cylindrical annulus. Laboratory experiments reveal two new principal regimes. In addition to the zonal circulation and wave regimes with different numbers of vortices we obtained a regime in which a wave was standing relative to the walls. The second is a vacillation regime in which vortices of different intensities form and drift at rates which vary with their positions relative to the regions of cooling and heating at the outer boundary. Theoretical analysis, based on a low-order Lorenz-type model, shows that it is possible to describe these regimes in terms of such a model. The study of the standing wave regime was made for uniform heating as well as for a different vertical temperature stratification. Some analogies with atmospheric blocking are discussed.