Experimental Wind Tunnel Investigation on Propeller–Wing
Interactional Aerodynamics
Shreyas Srivathsan
*
and Juergen Rauleder
†
Georgia Institute of Technology, Atlanta, Georgia, 30313
Recent advances in technology have enabled a range of electric-powered aircraft for missions
from package delivery to urban air taxi operations. Many of these designs rely on wingborne
flight using distributed electric propulsion or multiple propellers mounted on the wings. From a
safety and performance perspective, it is important to understand the physics and aerodynamic
phenomena, especially the aerodynamic interactions between single and multiple propellers
and wings, and their performance impact. Computational results exist, but due to the lack of
flight or ground test data for these novel vehicle configurations, the simulations often cannot be
verified and validated. This study aims to expand the current knowledge using model-scale wind
tunnel testing to understand the aerodynamic phenomena and performance effects associated
with, e.g., compound lift-and-cruise configurations or tiltrotors, by quantifying the loads on
the propeller and the wing. Measurements were done for a range of wing angles of attack,
freestream velocity, propeller rotational speed, propeller radius, and propeller–wing distance.
A significant wing drag decrease was found due to the presence of the propeller in front of the
wing, along with distinctive trends in lift curve slope as aforementioned variables were changed.
Propeller–wing distance significantly affected wing lift, drag, propeller performance, and the
combined propeller-wing system performance. This finding implies that for certain operating
conditions, the propeller–wing distance may be optimized to yield a better system performance,
which can be critical to increase the range for battery-powered aircraft that are often limited by
energy storage.
I. Nomenclature
(m
2
) = Propeller disk area,
2
= Wing aspect ratio,
2
(m) = Wing span
(m) = Wing chord
= Wing drag coefficient,
∞
= Sectional wing lift coefficient,
′
∞
= Wing lift coefficient,
∞
= Wing lift curve slope,
0
= Nominal wing lift curve slope from empirical data
ℎ
= Theoretical wing lift curve slope,
0
1+
0
= Propeller thrust coefficient,
3
4
∞
(
2
60
Ω )
2
=
∞
2
4
= Wing pitching moment coefficient,
∞
= Surface pressure coefficient along chord at wing midspan,
−
∞
∞
= Propeller torque coefficient,
4
4
∞
(
2
60
Ω )
2
=
2
∞
2
5
(m) = Propeller diameter, 2
−
(m) = Distance between propeller disk and wing leading edge at = 0
◦
(N) = Wing drag
*
Doctoral Candidate, Daniel Guggenheim School of Aerospace Engineering, sshreyas@gatech.edu
†
Assistant Professor, Daniel Guggenheim School of Aerospace Engineering, Associate Fellow AIAA, juergen.rauleder@gatech.edu
1
Downloaded by GEORGIA INST OF TECHNOLOGY on January 27, 2023 | http://arc.aiaa.org | DOI: 10.2514/6.2023-1752
AIAA SCITECH 2023 Forum
23-27 January 2023, National Harbor, MD & Online
10.2514/6.2023-1752
Copyright © 2023 by Shreyas Srivathsan and Juergen Rauleder. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission.
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