Simulation of manufacturing processes is a key step in achieving the digitalisation of manufacturing systems. This work presents the design, development and experimental evaluation of a discrete event simulation (DES) model of a production system (Festo Cyber-physical System). This model was used for the virtual analyses and optimisation of the production process and formed the basic framework for further virtual development of a digital twin of the physical asset. The factorial experimental technique was used to investigate the impact of identified factors of the physical system and their interactions on the system performance. Expert knowledge, generated data from the physical system and predefined objectives, were used to verify the virtual model.