화학공학소재연구정보센터
International Journal of Multiphase Flow, Vol.22, No.6, 1223-1246, 1996
Steady Suspension Flows into 2-Dimensional Horizontal and Inclined Channels
In this study a model which was developed previously is used to theoretically investigate the steady how of a particulate suspension into two-dimensional horizontal and inclined channels. The continuity equation for the fluid and the simplified two-dimensional Navier-Stokes equations are then solved together with a particle concentration equation. This latter equation is formulated by considering the balance between the particle flux due to gravity with the corresponding particle fluxes due to convection and shear-induced diffusion. The resulting coupled system of equations is solved numerically using a specialised finite-difference method. It is found, for the parameter range for hows of proppants in hydraulic fractures, that when the suspension enters the channel with a uniform velocity profile it almost instantaneously becomes parabolic. In addition, the effects of particle sedimentation are most dominant in the entrance region, but further downstream such effects are balanced as shear-induced particle diffusion becomes more important. It is also shown that the suspension how depends critically on the choice of the parameters used, e.g. the ratio of the particle radius to the height of the channel.