A finite volume formulation based on the 3D Chimera grid generation techniques was applied to numerical investigation of the small Reynolds number（9—50）local flows in fixed-bed reactors that were randomly packed with spheres.Due to the inhomogeneous distribution of porosity in the randomly packed fixed-beds，flow fields in fixed-beds are usually rather inhomogeneous.The present study investigated two different packed-bed configurations，which contained 120 and 500 spheres with diameter ratios（reactor diameter to sphere diameter） of 7 and 10.To achieve the resource-consuming computations，PVM-based distributed parallel computations were applied on a cluster parallel system.The numerical simulation results provided rather detailed information of the local flow fields in the fixed-beds and showed that there existed，in both of the fixed-beds，strong flow inhomogeneity，wall effects and channeling flows.