The high-fidelity modelling and simulation of the motion of a multiscale particulate fluid and its interaction with a structure is a challenging scientific problem of practical interest. In this lecture we present different advanced mathematical models and innovative numerical techniques for the accurate analysis of particulate flows containing particles of different sizes and their interaction with structures. The smaller particles will be homogenized with the carrier fluid via a new two-fluid approach using a physics-informed data-driven numerical simulation technique based on the pseudo-DNS approach [1]. Larger particles and objects interacting within the homogenized fluid will be modelled by enhanced discrete element methods [2]. Free surface particulate flows will be modelled with the Particle Finite Element Method (PFEM) [3,4]. Particle-based methods will be coupled to the finite element method for modelling the interaction between confined and free-surface particulate flows, large objects and rigid and deformable structures [5]. The model developments are applicable to a wide range of problems in engineering and applied sciences. In the paper we present selected examples of application to environmental particulate flows interacting with constructions and surface erosion in wind turbine blades due to their interaction with water raindrops [6].