ISBN 978-3-8439-5669-7

978-3-8439-5669-7, Reihe Ingenieurwissenschaften

Michael Valentin Schollenberger
Energetical Assessment of the Aerodynamic Interactions Between Propellers and Wings for Novel Aircraft Propulsion Concepts by Means of Numerical Simulation

245 Seiten, Dissertation Universität Stuttgart (2025), Softcover, A5

Zusammenfassung / Abstract

Even though propeller-driven aircraft are currently only used sporadically on very short flight routes, they have the potential to reduce emissions in the context of electric flight. In today's propeller-driven aircraft, unused energy remains in both the propeller slipstream and the wingtip vortex. This still usable exergy is preserved for a certain distance before it irreversibly dissipates into anergy. By the utilization of propeller-wing interactions, efficiency can be increased in cruise flight. Aircraft concepts specifically targeting these interactions are wingtip-mounted propellers (WTP) and distributed propulsion (DP). In the thesis, the interaction effects are considered energetically, both with regard to the processes within the flow field (e.g. the utilization of the mechanical exergy in the propeller slipstream) as well as with regard to the power balance of the aircraft as a whole.

In order to understand the interactions in more detail and to be able to compare the different concepts (WTP, DP) with regard to the increase in efficiency in cruise flight, a large number of propeller-wing arrangements are considered in the work. For this purpose, numerical simulations (CFD) based on Reynolds-averaged Navier-Stokes equations in steady-state and unsteady form (RANS/URANS) were carried out.

The interactions are discussed for increasingly complex propeller-wing arrangements and increasingly realistic inflow conditions. The evaluation was carried out using a classic force-based analysis as well as on an energetical level. In addition, the influence of design parameters is discussed and a comparison of the two fundamental concepts (WTP, DP) is made. In cruise flight, the pure WTP arrangement was identified as the most efficient configuration, followed by a partial distribution of two propellers per half-span, concentrated on the outer wing area. Aerodynamically optimized partial DP configurations could contribute to the reduction of aviation emissions.