Modeling Flows over Gravel Beds by a Body Force Method

Abstract

A new boundary condition for the three-dimensional Navier-Stokes equation and the vanishing viscosity limit J. Math. Phys. 53, 115617 (2012) Vortex stretching and criticality for the three-dimensional Navier-Stokes equations J. Math. Phys. 53, 115613 (2012) Flow past a normal flat plate undergoing inline oscillations Phys. Fluids 24, 093603 (2012) Conditional regularity of solutions of the three-dimensional Navier-Stokes equations and implications for intermittency J. Math. Phys. 53, 115608 (2012) Additional information on AIP Conf. Proc. Abstract A Reynolds-averaged Navier-stokes equations (RANS) model using the body force method (BFM) has been developed to simulate open-channel flows over gravel beds. The momentum equation is modified by introducing the form drag as an extra body force term to represent the gravel-bed resistance. By applying the body force within the roughness layer of the flow over small-scale roughness, it is found that the body force coefficient f rk varies inversely with the roughness length scale k s . The method is robust, not sensitive to mesh resolution and is easily extended to deal with large scale roughness.