GAMM2025

Session

S11: Interfacial flows

S11

8 Apr 2025, 16:30

Lecture and Conference Centre

Conveners

S11: Interfacial flows: S11.01

• Dirk Lucas
• Jacek Pozorski

S11: Interfacial flows: S11.02

• Jacek Pozorski
• Dirk Lucas

Description

The understanding and control of interfacial phenomena is one of the main challenges in multiphase fluid mechanics, at the crossroads of scientific disciplines like Mathematics, Physics, Chemistry and Engineering. Examples are particle-laden flows, bubble columns, flows with cavitation, jet atomization, casting, oil recovery, film, boiling and foaming flows, as well as spreading and dewetting of (complex) liquids and biofluids. All these systems are central for technological advances in the chemical, pharmaceutical, energy, environmental and food industries. In addition, their behavior depends strongly on the typical time and length scales under consideration that are for example crucial for the development of micro and nano fluidics. In the latter case the validity of continuum fluid mechanics might be even questionable. The goal of this section is to provide an overview of the latest developments in this area, covering models at different scales, numerical, statistical and cognitive methods as well as experimental techniques but also surveying new physical insight and recent technical advancements.

274. Arbitrary Lagrangian-Eulerian surface discretizations for self-evolving Navier-Stokes manifolds

Roger Sauer

08/04/2025, 16:30

A new arbitrary Lagrangian-Eulerian (ALE) formulation for area-incompressible Navier-Stokes flow on evolving surfaces is presented. The new formulation extends the surface ALE formulation of [1] to more general surface motions. It is based on a new curvilinear surface parameterization that describes the motion of the ALE frame. Its in-plane part becomes fully arbitrary, while its out-of-plane...

275. Two-Phase Flow Simulations Using Adaptive Time Refinement for Injection Molding Applications

Blanca Ferrer Fabón

08/04/2025, 16:50

In the field of polymer injection molding, high-resolution numerical simulations play a vital role in mitigating manufacturing defects. However, the complexity of these simulations presents significant challenges, and efficient numerical analysis remains an area of ongoing research.

In this study, we present a macro-scale two-phase flow formulation for polymer injection molding. We use an...

276. Advanced modelling of fibre dynamics in a transparent substitute liquid using the Jeffrey equation and PIV analysis

Tim Vaupel

08/04/2025, 17:10

The integration of fibres into high performance concrete and polymer matrices is to improve the durability and structural integrity of materials. A critical factor in achieving optimal resistance is the precise alignment of the fibres within the rigid matrix. Particle Image Velocimetry (PIV) is used to determine velocity vector fields within a specially designed test rig.

This was created...

277. Diffuse interface method for two-phase flows: development and validation, towards phase change modelling

Jacek Pozorski

08/04/2025, 17:30

We develop a computational approach for two-phase interfacial flows by applying the diffuse interface (DI) method based on the conservative Allen–Cahn equation. The weak compressibility (WC) is assumed in order to model low-speed flows; the mass and momentum are conserved. We report some modelling and numerical issues which are due to the WC assumption, along with the remedies proposed. In...

278. Phase-field modeling and computation of N-phase mixture flows

Marco ten Eikelder

08/04/2025, 17:50

The prototypical phase-field models for incompressible N-phase fluid mixtures are the Navier-Stokes Cahn-Hilliard models. Over the last few decades, many NSCH models with non-matching densities have been proposed. Even though these phase-field models aim to represent the same physical phenomena, they seem to differ at first sight. The first objective of this talk is to present a modeling...

279. High order Sharp Interface numerical methods for multiphase flows

Florian Kummer

09/04/2025, 08:30

This presentation focuses on the development and application of Extended Discontinuous Galerkin (XDG) methods which has been developed to simulate multiphase flows with high accuracy. From a numerical point of view, the challenge of multiphase flows is the low regularity of the solution. Due to abrupt changes in density and viscosity and due to surface tension effecte, there are...

280. Modelling multiscale multiphase flows with the MultiMorph Model

Dirk Lucas

09/04/2025, 09:10

Computational Fluid Dynamics becomes more and more important for industrial applications that involve multiphase flows. For such flows in medium and large scales the Euler-Euler approach is most frequently used and often the only feasible one. In many flow situations, the involved interfaces cover a wide range of scales leading to different coexisting morphologies. Established simulation...

281. Evolution of local bubble characteristics in a pressurised pneumatic flotation cell

Till Zürner

09/04/2025, 09:30

Flotation is used to separate particle intermixtures in many industrial applications, most notably in the mining industry for extracting valuable minerals from mined ores. During the flotation process, particles attach to air bubbles based on their hydrophobicity. More efficient recovery of fine and ultra-fine particles (smaller than 10 µm) benefits from highly turbulent flows and smaller...

282. Consistency of pseudopotential lattice Boltzmann methods in two-phase flow simulations of droplet dynamics

Luiz Eduardo Czelusniak

09/04/2025, 09:50

The pseudopotential method [Shan, Chen (1993), https://doi.org/10.1103/PhysRevE.47.1815] is a popular multiphase extension to the lattice Boltzmann method (LBM). Several improvements to the method have been proposed, allowing for better thermodynamic consistency, surface tension control, or stability for high density ratios [Czelusniak et al. (2020),...