In Pickering emulsions, Bijels and particle-stabilised foams the stabilisation mechanism rests on the formation of a semi-solid skin composed of one or more layers of particles on the fluid-fluid interface. Understanding the link between the rheological properties of this skin and the surface particle microstructure is a key challenge of modern multiphase flow and soft matter science . In this talk I will present FIPI, a new method for the fast simulation of particle-interface interaction problems involving bubbles, droplets and complex interfacial structures. This approximate method enables to simulate a large (up to O(105-106)) number of particles in a reasonable time on a common PC, and reach the length scale separation and time scales of realistic experimental systems. The idea of the method is to fully resolve interfacial and flow phenomena on a scale larger than the particle, and model particle-level phenomena with analytical or semi-empirical expressions. After describing the working principle of the method, I will illustrate the application of FIPI to two problems: the simulation of a pendant drop covered by a monolayer of purely repulsive spherical particles  and the shrinkage of a drop or bubble covered with a particle monolayer .
 C. Gu and L. Botto “Buckling vs. particle desorption in a particle-covered drop subject to compressive surface stresses: a simulation study”, Soft Matter, 14, 711, 2018
 C. Gu and L. Botto "Direct calculation of anisotropic surface stresses during deformation of a particle-covered drop", Soft Matter, 12, 705, 2016
 L. Botto et al. “Capillary interactions between anisotropic particles”, Soft Matter, 8, 9957, 2012