Computation Of Bed Shear Stresses In Natural Torrential Channels Using Smooth Particle Hydrodynamics

Flow in natural mountain torrents is very complex and typically characterized by non-linearity due to high roughness, steepness, wide range in torrent sediment sizes, presence of large woody debris, etc. Such flow is highly turbulent and difficult to describe with Eulerian grid-based methods. Smoothed Particle Hydrodynamics (SPH) method is a suitable Lagrangian method for modelling flow in typically rough and steep torrential streams. This paper introduces a new equation for the bed shear stresses using SPH. These new technique was verified and calibrated through two case studies (a. in a channel and b. in a natural torrential channel). Computed bed shear stresses in channel using SPH were also compared with computed bed shear stresses using other conventional method.