The problem of fluid flow in porous media has a paramount im- portant in the process, oil and metallurgical industries, since it is involved in the extraction of minerals and oil, in aquifers dynam- ics, as well as chemical reactions carried out in fixed bed catalytic reactors. Its CFD simulation is particularly interesting, as it offers the possibility of reducing the extent of costly experimental inves- tigations, but presents a number of technical challenges. One of the main issues is the generation of a geometrical model that real- istically represents the porous medium/particle packing. Its deriva- tion from experiments (i.e. micro-computer tomography) is compli- cated and packing codes are often limited to simple convex (mainly spherical) objects. In this work a computational tool developed in computer graphics, and integrated with the Bullet Physic Library, is used to generate realistic packings of polydisperse catalytic spheres and trilobes. The geometrical model is then meshed with Snap- pyHexMesh and then simulated with Ansys Fluent. Results show excellent agreement with experiments, demonstrating the great po- tentiality of the approach.