The HZDR multiphase addon contains additional code for the open-source CFD software OpenFOAM, released by The OpenFOAM Foundation. The developments are dedicated to the numerical simulation of multiphase flows, in particular to the multi-field two-fluid model (Euler-Euler method). Within the OpenFOAM library the multiphaseEulerFoam framework is used for this type of simulation. The addon contains a modified solver named HZDRmultiphaseEulerFoam with the full support of the HZDR baseline model set for polydisperse bubbly flows. In addition a solver dedicated to a hybrid modelling approach (dispersed and resolved interfaces, Meller, Schlegel and Lucas, 2021) named cipsaMultiphaseEulerFoam is provided with the addon. This solver has an interface to the multiphaseEulerFoam framework and utilizes all available interfacial models of it.

General enhancements

modified turbulent wall functions of Menter according to Rzehak and Kriebitzsch (2015)
dynamic time step adjustment via PID controller

HZDRmultiphaseEulerFoam

bubble induced turbulence model of Ma et al. (2017)
drag model of Ishii and Zuber (1979) without correction for swarm and/or viscous effects
wall lubrication model of Hosokawa et al. (2002)
additional breakup and coalescence models for class method according to Kusters (1991) and Adachi et al. (1994)
degassing boundary condition (fvModel)
lift force correlation of Hessenkemper et al. (2021)
lift force correlation of Saffman (1965) as extended by Mei (1992).
aspect ratio correlation of Ziegenhein and Lucas (2017)
real pressure treatment via explicit turbulent normal stress according to Rzehak et al. (2021)
GPU-based accelerated computation of coalescence and breakup frequencies for the models of Lehr et al. (2002) (Petelin et al., 2021)
configuration files and tutorials for easy setup of baseline cases according to Hänsch et al. (2021)

cipsaMultiphaseEulerFoam

morphology adaptive modelling framework for predicting dispersed and resolved interfaces based on Eulerian multi-field two-fluid model
compact momentum interpolation method according to Cubero et al. (2014), including virtual mass
numerical drag according to Strubelj and Tiselj (2011) to describe resolved interfaces in a volume-of-fluid like manner
n-phase partial elimination algorithm for momentum equations to resolve strong phase coupling (Meller, Schlegel and Lucas, 2021)
free surface turbulence damping (Frederix et al., 2018) for k-ω SST - symmetric and asymmetric - according to Tekavčič et al. (2021)
sub-grid scale modelling framework (Meller, Schlegel and Klein, 2021)

    additional LES models for the unclosed convective sub-grid scale term
    closure models for sub-grid surface tension term


configuration files and tutorials for easy setup of hybrid cases

This work was supported by the Helmholtz European Partnering Program in the project "Crossing borders and scales (Crossing)"

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