We investigate the entrance flow of a suspension modeled as a single inhomogeneous fluid. The inhomogeneity is due to non-uniform particles distribution on the vessel cross section. Our study aims to show that the particles migration towards the duct axis can also be explained as an entrance effect. The analysis is performed by generalizing the classical inertial terms linearization thus getting an autonomous system of two ODEs whose numerical solution is validated considering, as benchmark, the one correponding to the homogeneous flow. The results obtained indicate that the flow asymptotically reaches a core-annulus structure and that the particles migration towards the center essentially occurs in the entrance region. The drift is indeed governed by the transverse velocity which vanishes outside the entrance region. In particular, the migration away from the walls is substantially independent of the Reynolds number but inversely proportional to the viscosity of the suspension and therefore to the particles concentration. The Reynolds number affects the length of the entrance region.

我们研究了以单一非均匀流体为模型的悬架的入口流。不均匀性是由于容器横截面上的不均匀颗粒分布所致。我们的研究旨在表明粒子向风管轴的迁移也可以解释为进入效应。通过泛化经典惯性项线性化来进行分析，从而获得两个ODE的自治系统，其数值解已通过考虑与基准流对应的一个作为基准进行了验证。所获得的结果表明，流动渐近地达到了芯环结构，并且粒子向中心的迁移基本上发生在入口区域。漂移确实由横向速度控制，横向速度在入口区域之外消失。尤其是，离开壁的迁移基本上与雷诺数无关，但与悬浮液的粘度成反比，因此与颗粒浓度成反比。雷诺数会影响入射区域的长度。