In recent years computational fluid dynamics (CFD) has become a widely applied tool for the simulation of catalytic fixed-bed reactors and numerous authors have contributed towards methods for random packed bed generation and flow simulation. The presented approach focuses on an automated simulation routine realized through bash and python scripting covering multiple entire simulation runs including preprocessing, simulation as well as post-processing based on open-source software. As an example, the routine is demonstrated with a case study on catalytic fixed-bed reactors.