Knut Jørgen Måløy

Abstract Frictional fluid dynamics describes the displacement patterns that arise when a confined mixture of liquid and grains are displaced by an immiscible fluid under pressures that are too small to cause drainage into single pores. The flow, which is governed by solid friction and capillary forces, thus bulldozes the grains into compaction fronts which give rise to propagating fingers that eventually interact to create a range of patterns, including labyrinthine ones.

Abstract Multiphase flows involving granular materials are complex and prone to pattern formation caused by competing mechanical and hydrodynamic interactions. Here we study the interplay between granular bulldozing and the stabilising effect of viscous pressure gradients in the invading fluid.