Elasto-plastic flow of a foam around an obstacle

TL;DR

This paper simulates quasistatic 2D foam flows around various obstacles, analyzing pressure and network forces to understand how obstacle shape influences drag and lift, revealing linear drag increase and negative lift for aerofoil shapes.

Contribution

It provides new insights into foam flow dynamics around obstacles, highlighting the relationship between obstacle geometry and force contributions in a quasistatic regime.

Findings

Drag force increases linearly with obstacle cross section

Lift on asymmetric shapes is negative and grows with arc length

Pressure contribution mainly drives lift behavior

Abstract

We simulate quasistatic flows of an ideal two-dimensional monodisperse foam around different obstacles, both symmetric and asymmetric, in a channel. We record both pressure and network contributions to the drag and lift forces, and study them as a function of obstacle geometry. We show that the drag force increases linearly with the cross section of an obstacles. The lift on an asymmetric aerofoil-like shape is negative and increases with its arc length, mainly due to the pressure contribution.