Unlike a liquid rocket-engine, it is not possible to actively throttle the overall combustion of a solid rocket-motor. It is however possible to alter the thrust of an individual thruster by varying its throat area. The throat area can be altered by inserting a pintle of a conical or other shape into the nozzle throat. A setup which consist of multiple thrusters each with a pintle to alter its throat area, and which are connected to a single solid-propelled combustion chamber, can be used for attitude control of a rocket or spacecraft.

The goal of this thesis was to investigate the flow in a single thruster of such a system. For this purpose, a simple 1D simulation was developed. Additionally, multiple CFD simulations both static and dynamic were setup. The results of the simulations were then analysed in detail and compared amongst each other and with externally obtained test-data.