A numerical analysis of vortex shedding within a confined channel flow
AbstractThe numerical analysis of two-dimensional laminar vortex shedding from a rectangular cylinder within a confined channel flow is presented. This study, carried out using a computational fluid dynamics (CFD) code based on the SIMPLEST algorithm, considers the influence of numerical diffusion on the prediction of the vortex shedding frequency. The computational analysis compares the commonly used first-order accurate UPWIND scheme with the well-known third-order scheme QUICK and its derivative SMART, used for the discretization of convective transport. For the temporal differencing, a fully implicit scheme has been adopted. Plots of Strouhal number against Reynolds number suggest that the implementation of a higher-order scheme is beneficial for the accurate capture of the vortex shedding transient in unsteady flows of this nature.
In this study, two apparently similar clays have been characterised using advanced rheometry and particle-sizing techniques; the data and the blend design consequences are discussed. The analytical information has been used in the design of casting slips which have been characterised by both traditional and advanced methods. Special emphasis has been given to the interpretation of the rheological data and the particle size distributions and how these can be combined in order to optimise the casting performance of the system.