Summary The numerical solution of the population balance equation is frequently achieved by means discretization, ie, method classes. An important concern discrete formulations preservation 2 chosen moments distribution, eg, numbers and mass, while remaining flexible on grid kernels applied. Existing for breakage are either able to perserve only one moment or restricted choice kernels. Two types kernel functions description breakup rate exist, total model partial model. first type states a...

Abstract Polydispersity is a challenging feature of many industrial and environmental multiphase flows, influencing all related transfer transport processes. Besides their size, the fluid or solid particles may be distributed with respect to other properties such as velocity shape. Here, population balance model based on method classes combined multifluid solver within open source computational dynamics library OpenFOAM. The allows for tracking evolution one more size‐conditioned secondary...

Summary A morphology adaptive modeling framework is derived that able to handle computationally efficiently dispersed as well resolved interfacial structures coexisting in the computational domain with same set of equations. The Eulerian multifield two‐fluid model combined compact momentum interpolation method for multiple phases, which has been proposed literature an extension Rhie‐Chow pressure‐velocity coupling. Additionally drag force, virtual mass force consistently accounted model....

Abstract Open-source environments such as the Computational Fluid Dynamics software OpenFOAM are very appealing for research groups since they allow an efficient prototyping of new models or concepts. However, downstream developments to be sustainable, i.e. reproducible and reusable in long term, a significant amount maintenance work must accounted for. To growth extensibility, should underpinned by high degree automation repetitive tasks build tests, code deployment validation runs, order...

The two-fluid model is usually combined with closure forces designed for applications on coarse grids, i.e. bubbles (or particles) are typically assumed to be smaller than a grid cell. Practical however include situations were the mesh comparatively fine, e.g. when meshing wall boundary layer or in cases growing bubbles. This may lead non-convergent behaviour studies void fraction oscillations. To tackle this problem, filtering approach proposed, based an additional diffusion term continuity...

the atmosphere within turbulence closure models is mainly limited by a realistic three-dimensional (3D) representation of vegetation architecture. Within this contribution we present method to record 3D structure and use information derive model parameters that are suitable for numerical flow models. A mixed conifer forest stand around clearing was scanned represented dense point cloud applying terrestrial laser scanner. Thus, plant area density (PAD) with resolution one cubic meter provided...

Abstract Morphology‐adaptive multiphase models are becoming more established for the numerical description of complex gas‐liquid flows adapting dynamically to local flow morphology. In present study, two different methods originally designed distinct morphologies combined, namely volume‐of‐fluid and Euler–Euler method. Both edge cases have been proven be capable delivering reliable predictions in respective use cases. The long‐term goal is improve prediction flows, regardless regime a...

Predicting the agglomeration and breakage of solid particles is important when designing a compact efficient water purification process. A coupled computational fluid dynamics model presented where population balance equation applied to track particle size distribution for periodic turbulent pipe flow with 180° bends Reynolds numbers 15,000<Ref<35,000 bend radii rB=dh,rB=1.5dh rB=2.5dh. The critical parameters in Euler-Euler are analysed values chosen describe soot based on an experimentally...

Stratified flows are one of the most important multiphase flow regimes for safety analyses loss-of-coolant accident in pressurized water reactors. The present paper considers simulations an isothermal counter-current stratified case channel WENKA (Water Entrainment Channel Karlsruhe) experiment using a morphology adaptive multi-field two-fluid modelling framework. A consistent momentum interpolation approach is applied together with partial elimination algorithm, as it required strong...

Industrial multiphase flows are typically characterized by coexisting morphologies. Modern simulation methods well established for dispersed [e.g., Euler-Euler (E-E)] or resolved volume-of-fluid (VOF)] interfacial structures. Hence, a morphology adaptive multifield two-fluid model is proposed that able to handle and structures in the computational domain with same set of equations. An drag formulation large used describe them VOF-like manner. For structures, baseline developed at...

Modeling of annular flow with the computational fluid dynamics (CFD) is challenging as one has to consider several, rather different, phenomena simultaneously: continuous liquid film, gas core, and dispersed droplets. A morphology-adaptive multifield two-fluid model (MultiMorph) developed by Meller et al. [“Basic verification a numerical framework applied morphology adaptive considering bubble motions,” Int. J. Numer. Methods Fluids 93(3), 748–773 (2021)], three phase fields, well suited...

The Euler-Euler model is widely used in bubbly flow simulations up to industrial dimensions. standard based on the phase-averaging method. After averaging, bubble forces field equations are functions of local void fraction. In simulations, when diameter larger than computational cell spacing, can transport gas belonging same different directions. By contrast, a closure for force typically developed assumption that resultant acts bubble's center mass. This inconsistency lead nonphysical...

The morphology-adaptive multifield two-fluid model MultiMorph focuses on the reliable and robust simulation of interfacial multiphase flows in industrial applications. idea is to combine Volume-of-Fluid approach with Euler-Euler both large small scale structures efficiently. choice local representation structures, such as bubbles or droplets, by either first second aforementioned basic method strongly depends ratio length interface feature grid spacing. In case computational gets too coarse...