One-equation sub-grid scale (SGS) modelling for Euler–Euler large eddy simulation (EELES) of dispersed bubbly flow

Quantifying sub-grid scale (SGS) turbulent dispersion force and its effect using one-equation SGS large eddy simulation (LES) model in a gas–liquid and a liquid–liquid system

“…The Eulerian-Eulerian large eddy simulation (LES) turbulence model has shown significant promise in unearthing flow details in multiphase systems like, in gas-liquid multiphase systems (Deen et al, 2001;Dhotre et al, 2008;Tabib et al, 2008;Zhang et al, 2008;Niceno et al, 2008), in liquid-solid particle systems involving stirred vessel (Derksen, 2006), in fluidized bed (Chiesa et al, 2005) and particle laden flow (Riber et al, 2009). Though there is one drawback while applying the Eulerian-Eulerian LES, that is in-order to maintain the consistency of the assumption of interpenetrating continua, the largest interface details should be smaller than the grid size, which means that the cell size must be larger than the particle size.…”

Large Eddy Simulation for Dispersed Bubbly Flows: A Review

“…It was thought that in a case in which the bubbles actually drive the turbulence (via buoyancy and/or added mass forces), the situation would be different. However, in subsequent studies, similar observations were made in bubble plumes simulated by Deen et al [19], Dhotre et al [20], Ničeno et al [9]. The second approach for the modelling of BIT allows for the advective and diffusive transport of turbulent kinetic energy.…”

“…This pushes the main assumptions of the E-E approach to its limit of validity, and the grid is not fine enough for full interface tracking. In other words, the mesh requirement for E-E multiphase modelling conflicts with the requirements by LES approaches [9]. The issue of the requirement of the mesh size was first addressed by Milelli et al [11] who carried out a systematic analysis and performed a parametric study with different mesh sizes and bubble diameters.…”

“…[30]. Tabib and Schwarz [30] extended the work of Niceno et al [9] and attempted to quantify the effect of SGS turbulent dispersion force for different particle systems, where the particle sizes would be smaller than the filter size. They used LES with E-E approach.…”

“…The resolved part of the turbulent dispersion is implicitly computed. However, in case of a bubble size smaller than the filter size, turbulent transport can be present at SGS level and should be considered [9]. This can be done using a one-equation model, wherein it can be modelled by replacing the total kinetic energy by SGS contribution ( SGS ).…”