Proof of Concept for a New Altitude Test Facility for Electric Propulsors and Small Jet Engines

A new altitude test facility for small jet engines and electric propulsors is set up at the Institute of Jet Propulsion at the University of the Bundeswehr Munich. It will allow the investigation of turbo engines in a ground facility under ambient conditions corresponding to a flight in an altitude between 0km and 10km and a flight Mach number ranging from 0 to 0.9. In the scope of this paper, a 0D-simulation of the new altitude test facility is carried out using the software Simcenter AMESim in order to validate the developed concept, setup a preliminary control routine and gain knowledge about the behavior and limits of the test facility prior to commissioning. In addition to modeling the components of the test facility and the first engine to be tested, particular attention is devoted to the accurate representation of the ejector effect within the test chamber. For this purpose, a characteristic map is generated based on 3D CFD simulations, capturing the correlation of flow quantities at the test chamber's inlet and outlet under the influence of the ejector effect. This map is subsequently integrated into the 0D-simulation, enabling its consideration in the further analysis. With the 0D-simulation, the concept of the new altitude test facility is successfully validated and a basic concept for the control routine was elaborated. Finally, the facilities operating limits for operation with the first engine to be tested are derived from the simulation.