A Coupled, Constant Heat Flux Boundary Condition for CFD-DEM

The modeling of multiphase flows with a constant heat flux boundary has great practical and fundamental significance. Unlike their single-phase counterpart, multiphase systems experience coupling between phases and thus make the representation of a constant boundary flux non-trivial. Specifically, the partition of the total boundary flux between the phases can vary with space and time. A numerical technique for modeling such a boundary condition is proposed for gas-solids flows, and directly applied within a computational fluid dynamics and discrete element method (CFD-DEM) software. While simulations with discrete, monodisperse particles are considered here, the technique can be extended to polydisperse systems and/or the two fluid model.