Investigation of the interaction between the spacecraft and their electric thrusters before flight is a vital need for expensive satellite projects. This work is dedicated to simulating the interactions using a powerful ESA tool called Spacecraft Environment Interactions System (SPIS). Ions and neutrals are modeled with the particle-in-cell method, while the electrons are modeled with the fluid approach. The plume of the Hall-effect thruster SPT-100 is modeled and simulated, results are validated by comparing with the experimental data from literature. Afterwards, the plume is simulated...