During the preliminary design we assumed a thrust chamber pressure of 20 bar. To be able to test the engine without any risks on the area of the university, we chose the safety factors very conservativ, which results in a relatively large wall thickness. The advantage of this design is that there is no need for an active cooling, because the capacitive cooling effect of the engine is large enough.

The combustion inside the chamber has been calculated with the NASA Computer program CEA (Chemical Equilibrium with Applications). With this program you can calculate all relevant properties like the chamber temperature, specific impulse and many other. In the following diagram you can see clearly the dependency of the chamber temperature and the specific impulse from the mixture ratio r (= Oxidizer/Fuel).

The thust chamber was assembled from V2A stainless steel 1.4541.

For the calculation of the safety and strength we made extensive FEM-calculations.