Two‐fluid single‐column modelling of Rayleigh–Bénard convection as a step towards multi‐fluid modelling of atmospheric convection

Multi-fluid models have recently been proposed as an approach to improving the representation of convection in weather and climate models. This is attractive framework it fundamentally dynamical, removing some assumptions mass-flux schemes which are invalid at current model resolutions. However, still not understood how best close multi-fluid equations for atmospheric convection. In this paper we develop a simple two-fluid, single-column with one rising falling fluid. No further modelling sub-filter variability included. We then apply Rayleigh–Bénard convection, showing that, minimal closures, correct scaling heat flux ( N u ) predicted over six orders magnitude buoyancy forcing R ). suggests that even very two-fluid can accurately capture dominant coherent overturning structures