Wall modes and bulk convection in rapidly rotating Rayleigh-Bénard convection

We characterize the first transition to convection via wall mode instability and the nonlinear growth and instability of the resulting wall mode states including a secondary transition to time dependence. We describe how the transition to a state of bulk convection is influenced by the presence of the wall mode states and use temporal and spatial scales as measures of the local state of convection and heat transport Nu and momentum Re as representative of global transport. Our results elucidate the evolution of the wall state of rotating convection and confirm that wall modes and the BZF are strongly linked with the BZF being the robust remnant of nonlinear wall mode states. We also show how the heat transport Nu contributions of wall modes and bulk modes are related and how to disentangle their relative contributions.

[1] R.E. Ecke, X. Zhang, and O. Shishkina, Physical Review Fluids 7, L011501 (2022).