Smoothed particle hydrodynamics for the interaction of Newtonian and non-Newtonian fluids using the μ(I) model

The interaction between Newtonian and non-Newtonian fluid is one the most complicated problems for the engineers in the field of fluid mechanics. In the last decades, Lagrangian methods including smooth particle hydrodynamics has had the great interests among the different approaches in computational fluid dynamics (CFD). In this paper the collapse of the granular column and dry landslide and also two phase dam break and submerged landslide phenomena have been done through open source SPHysics2D code. The proposed model describes both fluid and sediment particles as weakly compressible flow where the sediment is treated as a non-Newtonian fluid using a viscoplastic model, called mu(I) model. This model is based on the properties of grains including inertia and friction coefficient. First, the performance of the viscoplastic code was investigated for a one- phase model by comparing the results measured in the laboratory and those obtained by developed code. Then, the movable dam break and submerged landslide phenomena were investigated, by the code developed for a two phase model, including Newtonian and non-Newtonian fluid. mu(I) viscoplastic model is utilized for the solid phase, Owen's equation and the mean harmonic viscosity are used to introduce the interactions between the particles containing different viscosities and densities. Results show that the model used in this research has reasonable accuracy by comparing with experimental models. (C) 2019 Elsevier B.V. All rights reserved.