Modelling thin film flow with erosion and deposition

A model is developed for the laminar flow of a thin film mixture made of water and particles over a surface with roughness of the same order as the film height. Particle erosion and deposition are also considered and modelled with two separate equations which are coupled to the fluid flow. This leads to a self-regulated erosion/deposition model, not requiring an explicit value for the transport capacity of the flow, this parameter appears analytically in the model. This approach is tested against a standard model for the erosion/deposition process. Algorithms are also developed to evaluate the required non-standard roughness parameters from experimental measurements and a numerical test of the model is carried out.