OpenFOAM

In 2020, CFD Direct were tasked to develop multicomponent diffusion modelling in OpenFOAM with funding from the Process Engineering Consortium. The Consortium need models, e.g. Maxwell-Stefan, that represent complex diffusion of species in fluid mixtures, affecting both specie concentration and energy. As part of the work, we created a new ThermophysicalTransportModels library with a new interfaces for: fluxes of heat, q() and divq(); and fluxes of mass, j() and divj(). As a consequence, heat transfer became consistent across applications, boundary conditions and data processing. This critical code redesign is typical of our strategy for sustainable development of OpenFOAM, supported by dedicated maintenance funding from OpenFOAM supporters.

In July 2020, CFD Direct released a framework for surface interpolation in interface capturing for multiphase flows in OpenFOAM. All interpolation schemes, used for flux calculation in advection, operate with the MULES-based solvers, e.g. interFoam. The framework is easy to use, extensible, and robust due to bounded, conservative numerics. The new framework comes with a new family of interpolation schemes based on piecewise-linear interface calculation (PLIC). The PLIC schemes provide a promising alternative to standard interface compression, performing better for meshes with regions of cell refinement. All schemes are conservative, bounded and robust and can run efficiently with large time steps.